Dissertations / Theses: 'Genetics'

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Hedmark, Eva. "Conservation Genetics of Scandinavian Wolverines." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Universitetsbiblioteket [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6636.

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De, Bustos Cecilia. "Genetic and Epigenetic Variation in the Human Genome : Analysis of Phenotypically Normal Individuals and Patients Affected with Brain Tumors." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6629.

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Fourie, Mariesa. "Molecular characterization and further shortening of recombinant forms of the Lr19 translocation." Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/189.

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Assefaw-Redda, Yohannes. "Hemolin expression during Cecropia development and its effect on malaria parasites." Doctoral thesis, Stockholm : Institutionen för genetik, mikrobiologi och toxikologi, Stockholms universitet, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-482.

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Sjödin, Per. "Effects of Selection and Demography on DNA Polymorphism in Black Mustard (Brassica nigra)." Doctoral thesis, Uppsala universitet, Evolutionär funktionsgenomik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6633.

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The evolution of three genes from the CONSTANS-LIKE gene family is studied in Brassica nigra. We use a combination of population genetic and phylogenetic techniques in order to assess the relative importance of selection and demography on the pattern of DNA variation. The analysis is complicated by the fact that they are recent duplicates of each other and hence there is a potential redundancy factor that has to be considered. The relationship between two of the genes, COa and COb, is however much closer than between any relationship to the third gene, COL1. The three genes are all suspected to play a part in the natural variation of flowering time of B. nigra. The thesis consists of four papers. The first paper is a technical paper concerning when and if the existence of an effective population size can be assumed. More specifically, the impact of population structure and a fluctuating (census) population size on the standard coalescent is studied. The second paper is a population genetic study of B. nigra using micro-satellites and RFLP. The resulting population genetic structure is argued to reflect the early spread of agriculture in Europe. In the third paper the general evolution of the three genes is studied. We find that not all aspects of the data could be accounted for by demography or redundancy effects, but that selection most likely played a part in the evolution of these genes. The fourth paper concerns the functional status of COb, whether it is a pseudogene or not. The most likely scenario is that COb recently became non-functional due to the fixation of a deleterious mutation during a recent bottleneck.

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Zenger, Kyall Richard. "Genetic linkage maps and population genetics of macropods." Phd thesis, Australia : Macquarie University, 2002. http://hdl.handle.net/1959.14/47604.

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"November 2001". Thesis (PhD)--Macquarie University, Division of Environmental and Life Sciences, Department of Biological Sciences, 2002. Bibliography: leaves 136-157. General introduction -- Molecular markers for comparative and quantitative studies in macropods -- Genetic linkage map construction in the tammar wallaby (M. eugenii) -- Intraspecific variation, sex-biased dispersal and phylogeography of the eastern grey kangaroo (M. giganteus) -- General discussion. The analysis of DNA using molecular techniques is an important tool for studies of evolutionary relationships, population genetics and genome organisation. The use of molecular markers within marsupials is primarily limited by their availability and success of amplification. Within this study, 77 macropodid type II microsatellite loci and two type I genetic markers were characterised within M. eugenii to evaluate polymorphic levels and cross-species amplification artifacts. Results indicated that 65 microsatellite loci amplified a single locus in M. eugenii with 44 exhibiting high levels of variability. The success of crossspecies amplification of microsatellite loci was inversely proportional to the evolutionary distance between the macropod species. It is revealed that the majority of species within the Macropodidae are capable of using many of the available heterologous microsatellites. When comparing the degree of variability between source-species and M. eugenii, most were significantly higher within source species (P < 0.05). These differences were most likely caused by ascertainment bias in microsatellite selection for both length and purity. -- The production of a marsupial genetic linkage map is perhaps one of the most important objectives in marsupial research. This study used a total of 353 informative meioses and 64 genetic markers to construct a framework genetic linkage map for M. eugenii. Nearly all markers (93.7%) formed a significant linkage (LOD > 3.0) with at least one other marker. More than 70% (828 cM) of the genome had been mapped when compared with chiasmata data. Nine linkage groups were identified, with all but one (LG7; X-linked) allocated to the autosomes. Theses groups ranged in size from 15.7 cM to 176.5 cM, and have an average distance of 16.2 cM between adjacent markers. Of the autosomal linkage groups, LG2 and LG3 were assigned to chromosome 1 and LG4 localised to chromosome 3 based on physical localisation of genes. Significant sex-specific distortions towards reduced female recombination rates were revealed in 22% of comparisons. Positive interference was observed within all the linkage groups analysed. When comparing the X-chromosome data to closely related species it is apparent that it is conserved both in synteny and gene order. -- The investigation of population dynamics of eastern grey kangaroos has been limited to a few ecological studies. The present investigation provides analysis of mtDNA and microsatellite data to infer both historical and contemporary patterns of population structuring and dispersal. The average level of genetic variation across sample locations was exceedingly high (h = 0.95, HE = 0.82), and is one of the highest observed for marsupials. Contrary to ecological studies, both genic and genotypic analyses reveal weak genetic structure of populations where high levels of dispersal may be inferred up to 230 km. The movement of individuals was predominantly male-biased (average N,m = 22.61, average N p = 2.73). However, neither sex showed significant isolation by distance. On a continental scale, there was strong genetic differentiation and phylogeographic distinction between southern (TAS, VIC and NSW) and northern (QLD) Australian populations, indicating a current and / or historical restriction of geneflow. In addition, it is evident that northern populations are historically more recent, and were derived from a small number of southern eastern grey kangaroo founders. Phylogenetic comparisons between M. g. giganteus and M. g. tasmaniensis, indicated that the current taxonomic status of these subspecies should be revised as there was a lack of genetic differentiation between the populations sampled. Mode of access: World Wide Web. xv, 182 leaves ill

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Souleman, Dima. "Genetic consequences of colonization of a metal-polluted environment, population genetics and quantitative genetics approaches." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10006/document.

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Les habitats naturels sont de plus en plus détruits et fragmentés par l'expansion urbaine et les activités humaines. La fragmentation des espaces naturels et agricoles par les bâtiments et les nouvelles infrastructures affecte la taille, la connectivité et la qualité des habitats. Les populations d’organismes vivants sur ces territoires anthropisés sont alors plus isolées. Or, la différenciation entre populations d’un même organisme dépend de processus démographiques et génétiques tels que la dérive génétique, le flux génétique, la mutation et la sélection naturelle. La persistance et le développement des populations dans des conditions environnementales modifiées dépendent de mécanismes de tolérance. Dans ce contexte, l'introduction de contaminants tels que des métaux dans l'environnement peut influencer l'évolution des plantes et des animaux en modifiant les forces évolutives et en créant des différences entre populations. Dans ce travail, l’attention a été portée sur les conséquences génétiques de la pollution métallique sur deux espèces, le ver de terre Lumbricus terrestris et une plante modèle Arabidopsis halleri. Deux approches différentes ont été utilisées pour étudier la réponse génétique à la contamination métallique : une approche de génétique des populations chez L. terrestris et une approche de génétique quantitative chez A. halleri. Tout d’abord, il s’est agi d’identifier et de valider de nouveaux marqueurs microsatellites chez L. terrestris. Ensuite, ces marqueurs ont été utilisés afin de caractériser la diversité génétique neutre chez des vers collectés sur des sites agricoles et urbanisés. Parallèlement, l'architecture génétique de la tolérance et de l'hyperaccumulation de Zn chez A. halleri a été explorée à l’aide d’un croisement intraspécifique entre une population métallicole et une population non métallicole. Une densité élevée de marqueurs SNP a été utilisée pour procéder à l'étape de cartographie QTL Natural habitats are more and more destructed and fragmented by urban expansion and human activities. The fragmentation of natural and agricultural areas by buildings and new infrastructures affects the size, connectivity and the quality of habitats. The populations of organisms inhabiting these anthropized territories are then more isolated. However, differentiation between populations of the same organism depends on demographic and genetic processes such as genetic drift, gene flow, mutation and natural selection. Only species that have developed special tolerance mechanisms can persist under changed environmental conditions. The introduction of contaminants such as metals in the environment may influence plants and animals evolution by modifying the evolutionary forces and thus generating differences between populations. In this work, attention was focused on the genetic consequences of metallic pollution on two species, the earthworm Lumbricus terrestris and the plant model Arabidopsis halleri. Two different approaches have been used to study the genetic response to metallic contamination: a population genetic approach was performed in L. terrestris and a quantitative genetic approach was carried on in A. halleri. First, it was a question of identifying and validating new microsatellite markers in L. terrestris. These markers were then used to characterize the neutral genetic diversity in worms collected from agricultural and urban sites. Secondly, genetic architecture of Zn tolerance and Zn hyperaccumulation was conducted investigated for the first time using an intraspecific crossing between metallicolous and non-metallicolous individuals of A. halleri. High density of SNP markers was used to proceed to the QTL mapping step

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Ennis, Don Gregory. "Genetics of SOS mutagenesis." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184602.

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Previous genetic evidence suggested that RecA was required in SOS mutagenesis for its regulatory role and perhaps some other nonregulatory role (Mount, 1977; Blanco et al., 1982). I undertook a genetic study which confirmed the above studies and provided further evidence that RecA protein appeared to have a dual "role in mutagenesis; first, the cleavage of LexA repressor for the derepression of specific SOS genes and second, one or more additional role(s). For these studies a new phage mutagenesis assay was developed which allows rapid scoring of SOS mutagenesis in a large number of host mutants. I next conducted a genetic analysis to determine if the newly defined RecA mutagenesis function was separable by mutation from the numerous other phenotypes which are known to be influenced by RecA protein. From the study of recA mutants it appears that the RecA mutagenesis function(s) is genetically separable from the following RecA phenotypes: LexA cleavage, lambda cI repressor cleavage, UV resistance and homologous recombination. In addition, I discovered that the LexA cleavage function and lambda cI cleavage function is also separable. I also studied in some detail the novel genetic properties that I uncovered for recA432 mutant strains. recA432 was defined as a mutagenesis defective allele (Kato and Shinoura, 1977). LexA cleavage in recA432 cells was more easily induced that in recA⁺ cells, causing lethal filamentation of these mutant cells even at very low UV doses. I concluded that the basis for the Mut⁻ phenotype was this strain's propensity to lethally filament, which complicated the detection of mutant cells. In another set of experiments, I examined the regulatory requirements for SOS mutagenesis and Weigle phage-reactivation; I wanted to determine which SOS operons must be derepressed for this process. lexA(Ind⁻) mutant cells are defective in mutagenesis because they cannot derepress specific SOS genes required in this process. I found that the selective derepression of umuDC was sufficient to restore mutagenesis to these lexA(Ind⁻) mutants; however, derepression of umuDC and recA was required for phage reactivation.

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Valvo, Giuseppe. "Applications of landscape genetics for wildlife conservation and management." Doctoral thesis, Università degli studi di Padova, 2011. http://hdl.handle.net/11577/3421998.

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In the last decade, the use of molecular markers revealing polymorphism at DNA level has played an increasing role in animal genetic and population studies. Amongst others, microsatellites have become the most widely employed markers, due to their easy use and to their high polymorphism that provides a large degree of information. Molecular markers are interesting and useful tools to assess genetic variability of species, breeds and populations, to infer population structure, to estimate genetic distances between breeds and individuals and also to define traceability methods for the identification of the origin of animal products for human consumption, a particularly important issue considering the widespread consumer demand for food safety. They are essential for the construction of genetic and physical maps and are increasingly used to assist selection and conservation plans. Moreover, they allow paternity and maternity tests, which can be a valid support to check genealogic information. Recently, molecular genetic markers have found wide application in the study of the interaction between landscape features and gene flow in natural populations. The first part of this thesis is aimed to apply an individual-based approach, with a panel of 25 microsatellites developed for roe deer (Capreolus capreolus), to examine the genetic structure of a natural roe deer population distributed over the the provinces of Trento and Belluno (north-esastern Italy. Georeferenced samples from a total of 657 roe deer, harvested in the hunting seasons 2003-2004 (for the samples of Belluno), and 2007-2008 and 2008-2009 (for the samples of Trento) were used.The results showed a significant heterozygosity deficit. The application of a Bayesian statistical approach, using the STRUCTURE and GENELAND programs, detected the presence of seven spatially separated subpopulations. The identification of hypothetical barriers was carried out by principal component analysis (PCA) using the software SURFER. The second part of the thesis is an application of the discipline “landscape genetics” assess whether the main landscape features that can be assumed as being relevant for roe deer ecology are associated with gene flow boundaries between subunits and with gene flow within subunits. Pairwise inter individual genetic distances (ar) were calculated with GENEPOP. To consider spatial and landscape distances between each pair of individuals, we calculated the Euclidean distance (the length of the straight line that connects one individual to another) and a “least cost distance” (the trajectory that maximizes the use of wooded corridors). To take into account other landscape features, we assigned a relative cost to each distance, which varied according to the proportion of potential obstacles to roe deer movement (high elevation areas, open areas, and urban areas). Finally, we analyzed, within each subpopulation, the correlation between pairwise genetic distances and the various geographic distances using Mantel test and Partial Mantel Test. The results showed that linear and least cost distances were correlated with gene flow in almost all populations, with slightly better values for least cost distances. Correlations improved when distances were weighed for land use and morphology costs, confirming that the assumed landscape features have an incidence on landscape connectivity for roe deer. In addition, the results suggested a difference in gene flow between males and females, although this indication should be better explored with a larger females sample. In conclusion, this approach is certainly very promising for studying the genetic and spatial structure of wild animal populations, and for identifying landscape features limiting gene flow. In the specific case of the studied roe deer population, the results obtained can help in devising ecologically meaningful management units and in understanding the species movement patterns-habitat features at a landscape scale. The increasing availability of specific GIS tools and and geographic databases, and the expected analytical improvements and cost reduction for molecular genetic markers, the applications of landscape genetics can certainly expand and provide information on microevolutionary processes and patterns of movement of wild animal populations Nell’ultimo decennio, l’uso di marcatori molecolari in grado di rilevare polimorfismi a livello del DNA ha acquisito sempre maggiore importanza nella genetica e nello studio delle popolazioni animali. I microsatelliti sono i più diffusamente impiegati, per la loro facilità d’impiego e il loro elevato polimorfismo, che li rende altamente informativi. I marcatori sono strumenti interessanti ed utili per evidenziare la variabilità genetica di specie, razze e popolazioni, per indagare la struttura delle popolazioni, per determinare distanze genetiche fra razze e individui e anche per la definizione di metodi di tracciabilità genetica al fine di identificare l’origine di prodotti animali destinati all’uomo, questione di particolare importanza data l’esigenza oramai diffusa di sicurezza da parte del consumatore. Essi sono decisivi per la costruzione di mappe genetiche e fisiche e sono sempre più studiati e impiegati a sostegno dei piani di selezione e conservazione. Consentono inoltre l’applicazione di test di paternità e maternità, e possono quindi contribuire al controllo delle informazioni genealogiche. L’obiettivo generale di questo lavoro è stato l’applicazione dell’analisi con microsatelliti ad una popolazione naturale di capriolo distribuita sul territorio delle province di Trento e Belluno, con l’individuazione di nuclei di sottopopolazioni da poter, eventualmente, utilizzare a fini gestionali. Infine, è stata condotta un’indagine sull’interazione fra le caratteristiche del paesaggio e la struttura genetica delle (sotto)popolazioni di capriolo identificate. Il primo contributo sperimentale comprende la messa a punto di un panel di 25 marcatori molecolari microsatellite per il capriolo (Capreolus capreolus) e la sua applicazione per l’identificazione della struttura genetica della popolazione di capriolo nelle province di Trento e Belluno, nelle Alpi orientali. La popolazione di capriolo è stata caratterizzata geneticamente per stabilire il livello di diversità genetica e per ricercare evidenze di un’eventuale strutturazione interna. Sono stati analizzati 657 campioni provenienti da capi abbattuti nelle province di Trento e Belluno nel corso delle stagioni venatorie 2003-2004 (per i campioni di Belluno) 2007-2008 e 2008-2009 (per i campioni di Trento). La caratterizzazione genetica effettuata sul campione analizzato ha dimostrato un forte deficit di eterozigosi. Sono stati applicati diversi approcci statistici per l’identificazione di eventuali sottopopolazioni e per l’identificazione di ipotetiche barriere. L’applicazione di un approccio statistico di tipo Bayesiano, utilizzando i software STRUCTURE e GENELAND, ha consentito di rilevare la presenza di sette sottopopolazioni, spazialmente separate, nell’intera area di studio. L’identificazione di ipotetiche barriere è stata effettuata tramite l’analisi delle componenti principali (PCA), utilizzando il software SURFER. Il secondo contributo sperimentale rappresenta un’applicazione della disciplina denominata “landscape genetics”, che consiste nello studio dell’interazione fra le caratteristiche del paesaggio e processi microevolutivi quali il flusso genico, la deriva genetica e la selezione. L’associazione fra struttura genetica e conformazione del territorio è stata quindi ulteriormente approfondita nel tentativo di identificare le variabili che hanno un ruolo maggiore nell’influenzare il flusso genico. Sono state calcolate tra ogni coppia di individui due tipi di distanze geografiche: la distanza euclidea (la lunghezza della linea retta che unisce un individuo ad un altro) e la distanza di minimo costo (la traiettoria che massimizza l'utilizzo dei corridoi di bosco per spostarsi da un luogo ad un altro). Sono state, successivamente, calcolate entro ciascuna popolazione le correlazioni fra le matrici di distanza genetica ottenute con GENEPOP e le corrispondenti matrici di distanze geografiche utilizzando due approcci statistici, il Mantel test e il Partial Mantel test. Queste correlazioni sono state verificate andando a considerare vari modelli del paesaggio, che hanno preso in considerazione diversi parametri quali la presenza di bosco, la presenza di insediamenti urbani, ecc. I risultati hanno dimostrato che tutte queste variabili incidono sulla connettività della popolazione. E’ stato messo in rilievo, inoltre, un differente impatto della struttura del territorio sui due sessi. Purtroppo, l'esiguo numero totale di femmine disponibili per ogni sotto-popolazione ha impedito un'adeguata analisi di questi sotto-campioni e il suo confronto con gli altri.. In conclusione, i risultati di questo lavoro hanno messo in luce, entro un’area geograficamente abbastanza limitata, l’esistenza di 7 sottopopolazioni di capriolo spazialmente separate che possono essere la base per la definizione di unità di gestione su base ecologica e non amministrativa. Inoltre, hanno fornito indicazioni a scala di paesaggio sulle relazioni fra la specie e l’uso e la morfologia del suolo. Da un punto di vista generale, inoltre, possiamo concludere che questo approccio è sicuramente molto promettente sia per studiare la struttura genetica e spaziale, e quindi evolutiva, delle popolazioni di animali selvatici, sia per affrontare con un criterio innovativo le relazioni fauna-ambiente. Il campionamento, se si tratta di specie cacciabili, è semplice e con costi modesti si possono ottenere numerosità consistenti. La possibilità di georeferenziare la localizzazione del singolo campione e di descrivere l’ambiente con strumenti di tipo GIS permette poi di collegare le informazioni genetiche a quelle ambientali e spaziali. Con l’ormai consolidata disponibilità di software GIS e basi cartografiche approfondite, e con la prevedibile diminuzione dei costi e l’affinamento delle indagini sui marcatori genetici molecolari, le applicazioni di landscape genetics potranno certamente estendersi e fornire indicazioni sulla storia recente, sugli scambi genetici e sulla dipendenza dai fattori ambientali delle popolazioni selvatiche.

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Lemons, Jennifer M. "“I didn’t know it existed until you called”: Protestant clergy experience and education of genetics." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1307125947.

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Moore, Rebekah Ann. "Provision of Genetics Services: Is it Time to Embrace Social Media?" Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1404902803.

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Somers, Allyson. "Provision of cardiovascular genetic counseling services: current practice and future directions." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1367924189.

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Ribeiro, Paulianny de Moura. "Diversidade e estrutura genética de Pilosocereus aureispinus: uma espécie de cactácea vulnerável e microendêmica." Universidade Federal de São Carlos, 2015. https://repositorio.ufscar.br/handle/ufscar/8358.

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Submitted by Maria de Lourdes Mariano (lmariano@ufscar.br) on 2017-01-10T13:10:23Z No. of bitstreams: 1 RIBEIRO_Paulianny de Moura_2015.pdf: 5411404 bytes, checksum: 0c49e97d507d656d40daf77bf7d00c91 (MD5) Approved for entry into archive by Maria de Lourdes Mariano (lmariano@ufscar.br) on 2017-01-10T13:10:33Z (GMT) No. of bitstreams: 1 RIBEIRO_Paulianny de Moura_2015.pdf: 5411404 bytes, checksum: 0c49e97d507d656d40daf77bf7d00c91 (MD5) Approved for entry into archive by Maria de Lourdes Mariano (lmariano@ufscar.br) on 2017-01-10T13:10:42Z (GMT) No. of bitstreams: 1 RIBEIRO_Paulianny de Moura_2015.pdf: 5411404 bytes, checksum: 0c49e97d507d656d40daf77bf7d00c91 (MD5) Made available in DSpace on 2017-01-10T13:10:51Z (GMT). No. of bitstreams: 1 RIBEIRO_Paulianny de Moura_2015.pdf: 5411404 bytes, checksum: 0c49e97d507d656d40daf77bf7d00c91 (MD5) Previous issue date: 2015-06-12 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Pilosocereus aureispinus (Buining & Brederoo) F. Ritter is a narrow endemic columnar cactus of eastern Brazil, occurring at Ibotirama and Oliveira dos Brejinhos, Bahia. In this work the genetic diversity and population structure were assessed for eight microsatellite loci in four P. aureispinus localities of occurrence, covering its known distribution. Genetic diversity levels were relatively high (A = 4,2 e HE = 0,451) comparing with closely related species and other narrowly distributed plant species. Significant Hardy-Weinberg Equilibrium departures and linkage disequilibrium were not detected. Private alleles in low frequencies and low levels of genetic structure (FST =0,071 e G”ST = 0,132) were detected. STRUCTURE software analysis did not identified structure, showing that samples from four analyzed localities represent a unique genetic group (K=1). These results pointed to high level of ongoing gene flow among sampled localities, which may counteract differentiation effects and genetic diversity loss. Despite P. aureispinus is not suffering genetic variability erosion due its narrow distribution, the species should be classified as endangered (EN) at IUCN Red List of Threatened Species due existent anthropogenic disturbs in regions where it occurs. Pilosocereus aureispinus (Buining & Brederoo) F. Ritter é um cacto colunar microendêmico e com distribuição restrita na porção do leste do Brasil, na região dos municípios de Ibotirama e Oliveira dos Brejinhos, Bahia. Nesse trabalho foram estimados os níveis de diversidade genética e estruturação populacional a partir de oito locos de DNA microssatélite em quatro localidades de ocorrência de P. aureispinus, abrangendo sua distribuição conhecida. Os níveis de diversidade genética foram relativamente altos (A = 4,2 e HE = 0,451) quando comparados com outras espécies proximamente relacionadas e com espécies de distribuição restrita. Não foram detectados locos com desvios significativos em relação às proporções do Equilíbrio de Hardy-Weinberg e desequilíbrio de ligação. Alelos exclusivos foram detectados em baixa frequência, assim como baixos níveis de estruturação genética (FST = 0,071 e G”ST = 0,132). A análise no programa STRUCTURE não identificou estruturação, indicando que as amostras das quatro localidades analisadas representam apenas um grupo genético (K=1). Esses resultados permitem inferir que há acentuado fluxo gênico recente entre as localidades amostradas, o qual pode neutralizar os efeitos de diferenciação e a perda de diversidade genética. Embora nossos resultados indiquem que P. aureispinus não esteja sofrendo perda de variabilidade genética devido à sua distribuição restrita, a espécie deveria ser classificada como ameaçada (EN) na Lista Vermelha de Espécies Ameaçadas da IUCN devido aos distúrbios antrópicos existentes nas regiões onde ocorre.

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Sikora, Martin. "Evolutionary genetics of malaria: genetic susceptibility and natural selection." Doctoral thesis, Universitat Pompeu Fabra, 2010. http://hdl.handle.net/10803/7220.

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Una de les forces selectives més fortes que han afectat a les poblacions humanes en la història més recent és el paràsit de la malària: Plasmodium falciparum, que és la causa de varis exemples d'adaptació induïda per patògens en els éssers humans. Una forma especial de malària és l'associada a l'embaràs, que es caracteritza per l'acumulació d'eritròcits infectats en la placenta, i que pot arribar a causar fins a 200.000 morts maternoinfantils cada any. L'objectiu d'aquest treball és descriure com aquesta forma peculiar de malària ha afectat la variació genètica humana. Amb aquesta finalitat, hem utilitzat mètodes tant de la genètica evolutiva com de l'epidemiologia molecular, resultant en la primera investigació a gran escala de la base genètica de la malària placentària. Els resultats ofereixen una nova visió sobre els gens que modulen el risc d'infecció, ,així com de la selecció natural actuant sobre les vies cel·lulars implicades en la patogènesi de la malaltia. Finalment, també aportem noves dades sobre l'estructura genètica de les poblacions sub-saharianes analitzades. One of the strongest selective forces affecting human populations in recent history is the malaria parasite Plasmodium falciparum, which is the cause of a variety of well-established examples of pathogen-induced adaptation in humans. A special form of malaria is pregnancy-associated malaria, which is characterised by the accumulation of infected erythrocytes in the placenta, and causes up to 200,000 maternal and infant deaths every year. The aim of this work is to characterise how this particular form of malaria has shaped human genetic variation. To that end we use methods of both evolutionary genetics and molecular epidemiology, reporting the first large-scale investigation of the genetic basis of placental infection. Our results provide new insights into genes modulating the risk of infection, as well as natural selection acting on cellular pathways involved in the pathogenesis of the disease. Finally, we also provide new data on the genetic structure of affected populations in Sub-Saharan Africa.

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Rodas, Perez M. C. "Medical genetics in Colombia : genetic consultation and counselling in five genetic clinics." Thesis, University of Warwick, 2012. http://wrap.warwick.ac.uk/46980/.

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Today genetic services including genetic counselling are widespread across the world. Although developing countries, like Colombia, have started to apply genetic knowledge to the health area, genetic counselling is usually integrated in the routine clinical genetic consultation, however, before this study the process of communication involved in it had not been explored. In collaboration with the Colombian Association of Medical Genetics, the Bogotá Health Service, and the University of Warwick (UK), I observed 25 genetic consultations in five Colombian genetic clinics. I undertook semi-structured interviews with patients / families before and after the consultation. Thematic analysis of the interview transcripts established mismatches between physician perception and patient comprehension. Efficient communication was affected by patient, relatives, practitioner and external factors. Among these environmental factors were excessive administrative procedures, interruptions during the encounter, patients‟ lack of interest to medical terminology, doctors using scientific language, excessive information given in one session, beliefs and education level of the patient and/or relatives, patient distress caused by bad news, unfulfilled expectations and no availability/accessibility of treatment. I also interviewed 20 medical practitioners working in genetics services. There was general agreement that genetic counselling in Colombia was challenging, and that more training in communication skills was required at Medical schools at undergraduate and postgraduate level. Many physicians did not believe that other health professionals should work as genetic counsellors. There was a general recognition of limited genetic knowledge, awareness and understanding in most medical specialities. These results have made a valuable contribution to describe the current situation with genetics consultation and counselling in Colombian genetic clinics, and have already influenced the future development of an effective and robust genetic counselling service in Colombia. They will also be used in the development of the academic curriculum related to basic and clinical genetics at Colombian Universities.

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Asher, Allison Marie. "CONSERVATION GENETICS OF PADDLEFISH: GENETIC EFFECTIVE POPULATION SIZE AND RANGEWIDE GENETIC STRUCTURE." OpenSIUC, 2019. https://opensiuc.lib.siu.edu/dissertations/1693.

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Paddlefish (Polyodon spathula) is a commercially and recreationally important species, with a native range that extends over 22 US states. This is a large, long-lived, highly mobile riverine species that has been negatively impacted by habitat fragmentation, historic overharvest, and hatchery supplementation. Dams are the primary cause of habitat fragmentation, blocking migration routes, flooding spawning grounds, and isolating populations. A common management action to mitigate the impacts of habitat fragmentation and maintain harvestable populations is hatchery propagation and stocking. Reduction in stock size, isolation of populations, and stocking can all negatively impact the genetic integrity of Paddlefish. I evaluated the impacts of isolation and hatchery supplementation on the effective population size (Ne) of Paddlefish as well as the range-wide genetic structure of Paddlefish.

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Bruiners, Natalie. "Molecular genetic analysis of preterm labour." Thesis, Stellenbosch : Stellenbosch University, 2007. http://hdl.handle.net/10019.1/17741.

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Thesis (MSc)--University of Stellenbosch, 2007. ENGLISH ABSTRACT: The World Health Organisation (WHO) has defined preterm labour as the onset of labour before 37 completed weeks of gestation with an incidence ranging between 5-10%. Although patient care has improved, the rate of preterm birth has slowly been increasing and currently impacts significantly on maternal and fetal mortality and morbidity. The complex condition of preterm labour involves multiple etiologies and risk factors, which complicates the search for candidate markers and / or biomarkers. The aim of this prospective study was to investigate potential genetic associations with preterm labour. The study cohort consisted of consecutive first-time booking, low-risk primigravid pregnant women from a restricted geographical region. The study cohort comprised 421 [306 Coloured and 115 Black] pregnant women presenting at the Paarl Hospital Obstetric clinic. Subsequently, DNA was extracted from whole blood and investigated for a range of known polymorphisms in pro-inflammatory and anti-inflammatory cytokines, as well as the novel LGALS13 gene, for potential variants that may impact on pregnancy outcome. Screening techniques involve combinations of allele-specific PCR amplification, Multiphor SSCP/HD analysis, restriction enzyme analyses and DNA sequencing. A significant association was demonstrated between the IL-1RN*2-allele and adverse pregnancy outcome, mainly in the preterm labour and hypertension group. The presence TNFα-308 A-allele was associated with overall adverse pregnancy outcome and preterm labour. In addition to this, a novel IL-1RN allele was identified in the control group. Mutation screening and subsequent statistical methods revealed an association between a novel LGALS13 exonic variant, 221delT, and preterm labour in Coloured women. Two previouslydocumented intronic variants (IVS2-22A/G and IVS3+72T/A) demonstrated linkage disequilibrium, signifying evolutionary conservation of exon three. Additionally, two novel intronic variants, IVS2-36 G/A and IVS2-15 G/A, demonstrated no association with adverse pregnancy outcome. In this study we identified rare novel exonic variants; two non-synonymous variants in exon three (M44V, [N=2] and K87R, [N=1]) and a silent variant in exon four (P117P, [N=1]) - all identified in individuals from the control cohort. Within coding exon three, an interesting variant [“hotspot”] was identified, which represents six polymorphic bases within an 11bp stretch. No associations were demonstrated with these variants and pregnancy outcome. Furthermore, a previously documented 5' “‘promoter” variant, -98 A/C, was identified and demonstrated no association with adverse pregnancy outcome. However, subdivision of lateonset pre-eclamptic cases revealed a significant association with the A-allele and late-onset preeclampsia. Genotype-phenotype investigation demonstrated association between the IL-10 -1082 A/G, IL-4 C/T and 221delT loci and poor pregnancy progress which manifested as (i) delivery of infants weighing <2000g, (ii) before 37 weeks of gestation. The findings of this study will strengthen our understanding of the pathophysiology underlying pregnancy complications and facilitate the further development of effective treatment strategies to reduce maternal and fetal morbidity and mortality. AFRIKAANSE OPSOMMING: Die Wêreld Gesondheid Organisasie (WHO) klassifiseer voortydse kraam as kontraksie voor 37 volledige weke, met ‘n insidensie tussen 5-10%. Alhoewel pasiënte-sorg verbeter het, neem die tempo van voortydse geboorte steeds toe, wat ‘n groot impak het op moederstrefte en fetale mortaliteit en morbiditeit. Die komplekse kondisie van voortydse kraam sluit veelvoudige oorsake en risiko faktore in, wat die navorsing van kandidaat en / of biologiese merkers kompliseer. Die doel van hierdie prospektiewe studie, was die potensiële navorsing van genetiese assosiasies met voortydse kraam. Die studie kohort bevat opeenvolgende eerste bespreking van lae risiko primigravida swanger vrouens vanaf ‘n beperkte geografiese omgewing. Die studie kohort beslaan 421 [306 Kleurling en 115 Swart] swanger vrouens teenwoordig by die Paarl Hospitaal Verloskunde kliniek. Vervolgens was DNS geëkstraeer van bloedmonsters en geondersoek vir ‘n verskeidenheid van bekende polimorfismes in pro-inflammatoriese en antiinflammatoriese sitokiene, insluitend die nuwe sifting van die LGALS13 geen potensiaal vir variante wat ‘n impak op swangerskap uitkomste sal hê. Die siftings tegnieke toegepas, sluit in ‘n kombinasie van alleel-spesifieke amplifikasie, Multiphor enkelstring konformasie polimorfisme / heterodupleks analise, restriksie ensiem verterings en volgorde bepalings tegnieke. ‘n Betekenisvolle assosiasie was gedemonstreer tussen die IL-1RN*2-alleel en nadelige swangerskap, beperk tot voortydse kraam en die hipertensie groep. Die teenwoordigheid van die TNFα-308 A-alleel was geassosieer met algehele nadelige uitkomste en voortydse kraam. Daarby, was ‘n nuwe IL-1RN alleel geïdentifiseer in die kontrole groep. Mutasie sifting en opeenvolgende statistiese metodes, het ‘n assosiasie getoon tussen ‘n nuwe LGALS13 koderende variant, 221delT, en voortydse kraam in Kleurling vrouens. Twee voorafbeskryfde introniese variante (IVS2-22 A/G en IVS3+72 T/A), het ‘n betekenisvolle bewys opgelewer dat daar koppelings-onewewig bestaan tussen hierdie variante, en toon evolusionêre konservasie van ekson drie. Addisioneel was twee nuwe introniese variante ontdek, IVS2-36 G/A en IVS2-15 G/A, wat geen assosiasie getoon nie. In hierdie studie het ons ‘n nuwe seldsame koderende variante geïdentifiseer in die kontrole groep, waarvan twee nie-sinonieme variante was in ekson drie (M44V, N=2 en K87R, N=1) en ‘n stil variasie in ekson vier (P117P, N=1). Geleë in die koderende area van ekson drie, was ’n interessante variant [“hotspot’] ontdek, waarvan ses basisse in ‘n 11 basis paar area polimorfies is. Geen assosiasie was getoon met hierdie variante en swangerskap uitkomste nie. Verder was ‘n voorafbeskryfde 5' ‘promotor’ variant, -98 A/C, geïdentifiseer wat geen assosiasie getoon met nadelige swangerskap uitkomste nie. Onderverdeling van laat-aanvangs preeklampsie, het getoon dat die A-alleel ‘n betekenisvolle assosiasie getoon het met die ontwikkeling van laat pre-eklampsie. Genotipe-fenotipe interaksies het ’n assosiasie getoon tussen die IL-10 -1082 A/G, IL-4 C/T en 221delT lokusse en nadelige swangerskap uitkomste, wat manifesteer as (i) kraam van suigelinge wat <2000g weeg, (ii) geboorte voor 37 weke. Die bevindings van hierdie studie sal ons basiese kennis verbeter oor die patologie beskrywend aan swangerskap komplikasies, asook die fasilitering en ontwikkeling van effektiewe behandelings strategieë, om moederstrefte en fetale mortaliteit en morbiditeit te verminder.

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Bitalo, Daphne Nyachaki. "Implementation of molecular markers for triticale cultivar identification and marker-assisted selection." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71670.

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Thesis (MSc)--Stellenbosch University, 2012. Triticale is an amphidiploid that consists of wheat (A and B) and rye (R) genomes. This cereal is fast becoming important on a commercial basis and warrants further assessment for the better management and breeding of the hybrid. The assessment of the genetic diversity among the wheat and rye genomes within triticale can be obtained by using molecular markers developed in both donor genomes. Simple sequence repeats markers (SSRs) and amplified fragment length markers (AFLPs) have been previously used to assess the genetic diversity among triticale lines. SSRs are highly polymorphic markers that are abundant and which have been shown to be highly transferable between species in previous studies while AFLP markers are known to generate plenty of data as they cover so many loci. Thus, the aim of this study was to develop a marker system suitable to assess the genetic diversity and relationships of advanced breeding material (and cultivars) of the Stellenbosch University’s Plant Breeding Laboratory (SU-PBL). Therefore, both AFLP and SSR markers were initially analysed using eight triticale cultivars (with known pedigrees) to facilitate cultivar identification. Fourty-two AFLP primer combinations and 86 SSR markers were used to assess the genetic diversity among the Elite triticale cultivars. The AFLP primer combinations generated under average polymorphism information content (PIC) values. Furthermore, these markers generated neighbour-joining (NJ) and unweighted pair group method with arithmetic average (UPGMA) dendograms that displayed relationships that did not correspond with the available pedigree information. Therefore, this marker system was found not to be suitable. A set of 86 SSRs previously identified in both wheat and rye, was used to test the genetic diversity among the eight cultivars. The markers developed in wheat achieved 84% transferability while those developed in rye achieved 79.3% transferability. A subset of SSR markers was able to distinguish the cultivars, and correctly identify them by generating NJ and UPGMA dendograms that exhibited relationships that corroborated the available pedigree data. This panel of markers was therefore chosen as the most suitable for the assessment of the advanced breeding material. The panel of seven SSR markers was optimised for semi-automated analysis and was used to screen and detect the genetic diversity among 306 triticale entries in the F6, Senior and Elite phases of the SU-PBL triticale breeding programme. An average PIC value of 0.65 was detected and moderate genetic variation was observed. NJ and UPGMA dendograms generated showed no clear groupings. However, the panel of markers managed to accurately identify all cultivars within the breeding program. The marker panel developed in this study is being used to routinely distinguish among the advanced breeding material within the SU-PBL triticale breeding programme and as a tool in molecular-assisted backcross.

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Van, den Berg Nicol-Candice. "Microsatellite marker development and parentage assignment in Haliotis midae." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/21911.

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Thesis (MSc)--University of Stellenbosch, 2008. ENGLISH ABSTRACT: The five leading abalone producers in South Africa have initiated a genetic enhancement program for Haliotis midae in a collaborative effort to improve economically valuable traits. Several independent objective-specific studies were initiated, including the establishment of a Performance Recording Scheme (PRS), utilised in this study, and necessary to monitor the ongoing performance of individuals as the move from mass-selection to marker assisted selection (MAS) is implemented. The primary objective of this study was parentage assignment of F1 offspring mass-selected for size at approximately one year and allocated to either a “faster” or a “slower” growth group. Nine microsatellite markers were used to genotype juveniles and potential parents, with assignment completed using CERVUS 2.0. Average growth results for Abagold and HIK were comparable for both growth groups. Slight environmental effects, although not statistically significant, were evident as growth advantages for juveniles within the faster growth group at two of the five locations and for juveniles within the slower growth group at one of the five rearing locations. Despite measures to standardise environmental influences, variables are difficult to control within the reality of a production environment; and potential genotype x environment interactions may require further investigation and factoring into future breeding programs. The additional costs associated with MAS often make the technology prohibitive to most aquaculture operations, despite the significant genetic gains to be realised from its implementation. Cost-optimising routine processes such as DNA extractions may be one approach to reduce these additional costs. Chelex®100 appears to be a suitable alternative to the CTAB method – being quick and cost-effective to perform. Applying this method in combination with the high throughput of a robotic platform warrants further evaluation. For the microsatellite development, 50% of positive recombinant clones contained inserts. Sequencing of these clones produced 16% perfect repeats and 47% imperfect repeats for which 52 primer sets were designed and tested. In total, 31 polymorphic microsatellite loci of different motifs and composition were developed. Sixty-one percent of sequenced clones were deemed redundant and pre-screening for both uniqueness and the presence of microsatellites would reduce unnecessary sequencing thus improving the efficiency of the FIASCO method and reducing costs. Nine loci were selected for parentage assignments. Null alleles were present for all the selected markers; however, frequencies were below the critical level of 5%. Parentage yielded 91% and 90% successful assignment for Abagold and HIK respectively; however, observations indicate that a measure of relatedness may exist between breeders. Recommendations with regards to future family breeding include, for both Abagold and HIK, retaining selected breeders based on their respective contributions to the F1 progeny while reassessing the potential of remaining breeding stock under more controlled breeding conditions. No obvious trends were observed for growth with most individuals producing both faster and slower growing offspring. Juveniles will be reassessed at two years to determine whether the size advantage or disadvantages were maintained and to ascertain whether growth advantages/disadvantages may be gender specific. AFRIKAANSE OPSOMMING: Die vyf mees toonaangewende perlemoen produseerders in Suid Afrika het „n genetiese verbeteringsprogram vir Haliotis midae geinisieer in „n gesamentlike poging om ekonomiese belangrike eienskappe te verbeter. Verskeie onafhanklike fokus-spesifieke studies is geinisieer, insluitend die totstandkoming van „n groeiprestasie aantekenstelsel, soos gebruik in hierdie studie, en wat noodsaaklik is om die aaneenlopende prestasie van individue te moniteer soos daar beweeg word van massa seleksie tot merker bemiddelde seleksie. Die primêre fokus van hierdie studie was die ouerskapsbepaling van F1 nageslag wat massa geselekteer is op ouderdom 1 jaar vir grootte en as of “vinniger” of “stadiger” groeiers geklassifiseer is. Nege mikrosatelliet merkers is gebruik om jong perlemoen individue en moontlike ouers te genotipeer, met die ouerskapstoekenning bereken deur CERVUS 2.0. Groei resultate vir Abagold en HIK was vergelykbaar vir beide groei groepe op drie van die lokaliteite. Geringe omgewingseffekte, alhoewel nie statisties betekenisvol nie, was sigbaar as „n groei voordeel vir jong individue op twee van die vyf lokaliteite. Ongeag maatstawe om omgewingsinvloede te standardiseer, is varieerbares moeilik om te beheer in die produksie omgewing en genotipe x omgewings interaksies mag verdere navorsing vereis en behoort in ag geneem te word in toekomstige telingsprogramme. Die onkoste wat met merker bemiddelde seleksie geassosieer word, maak die tegniek soms onaantreklik vir die meeste akwakultuur operasies; nie teen staande die genetiese voordele wat die gebruik daarvan veroorsaak. Die koste-optimiseering van roetine prosesse, soos byvoorbeeld, DNA ekstraksies, is dalk een aanslag om die addisionele koste te verminder. Chelex®100 blyk „n geskikte alternatief tot die CTAB metode te wees – die tegniek is vinnig en koste-effektief om uit te voer. Die gebruik van hierdie metode in kombinasie met die hoë deurvloei van ‟n robotiese sisteem behoort verder ondersoek te word. Vir die mikrosatelliet ontwikkeling het slegs 50% van die positiewe rekombinante klone invoegings bevat. Nukleotiedvolgorde bepaling van hierdie klone het 16% perfekte herhalings en 47% onderbroke herhalings bevat waaruit 52 inleierstelle ontwikkel en getoets is. In totaal is 31 polimorfiese mikrosatelliet loki van verskillende motiewe en samestelling ontwikkel. Een-en-sestig persent van die volgorde bepaalde klone is oortollig geag en vooraf sifting vir beide uniekheid en die teenwoordigheid van mikrosatelliete sal onnodige volgorde bepaling verhoed, die effektiwiteit van die FIASCO tegniek verhoog sowel as addisionele koste verminder. Nege loki is geselekteer vir ouerskapsbepaling. Nul allele was teenwoordig vir al die geselekteerde merkers, maar die frekwensies was egter laer as die 5% kritieke waarde. Ouerskap is 91% en 90% suksesvol bepaal vir Abagold en HIK onderskeidelik. Waarnemings dui egter daarop dat daar verwantskappe mag wees tussen van die broeidiere. Voorstelle in terme van toekomstige familie teling sluit is, vir beide Abagold en HIK, om geselekteerde broei diere te behou gebaseer op hulle onderskeie bydraes tot die F1 nageslag asook die herevaluaring van die potensiaal van die oorblywende broei diere onder meer beheerde teling toestande. Geen voor-die-handliggende tendense is waargeneem vir groei nie met die meeste individue wat beide vinniger en stadiger groeiende nageslag geproduseer het. Jong individue moet geherevalueer word op tweejarige ouderdom om te bepaal of die groei voordeel of nadele behou is en om te bepaal om groei voordele/nadele geslagspesifiek is.

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Nicholls, Felicity K. M. "Genetic analysis of the gene Additional sex combs and interacting loci." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29644.

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In order to recover new mutant alleles of the Polycomb group gene Additional sex combs (Asx), mutagenized chromosomes were screened over the putative Asx allele XT129. Thirteen new mutant strains that fail to complement XT129 were recovered. Unexpectedly, the thirteen strains sorted into four complementation groups. Recombination mapping suggests that each complementation group represents a separate locus. The largest group fails to complement a deletion of Asx and maps in the vicinity of 2-72, the published location of Asx. All new mutant strains enhance the phenotype of Polycomb mutant flies and are not allelic to any previously discovered second chromosome Polycomb group genes. Therefore, the new mutants may be considered putative new members of the Polycomb group. This study suggests that Asx belongs to a sub-group of genes displaying intergenic non-complementation. Science, Faculty of Zoology, Department of Graduate

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Ingman, Max. "Mitochondria and Human Evolution." Doctoral thesis, Uppsala University, Department of Genetics and Pathology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3580.

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Mitochondrial DNA (mtDNA) has been a potent tool in studies of the evolution of modern humans, human migrations and the dynamics of human populations over time. The popularity of this cytoplasmic genome has largely been due to its clonal inheritance (in Man) allowing the tracing of a direct genetic line. In addition, a comparatively high rate of nucleotide substitution facilitates phylogenetic resolution among relatively closely related individuals of the same species.In this thesis, a statistically supported phylogeny based on complete mitochondrial genome sequences is presented which, for the first time, unambiguously places the root of modern human mitochondrial lineages in Africa in the last 200 thousand years. This conclusion provides strong support for the “recent African origin” hypothesis. Also, the complete genome data underline the problematic nature of traditional approaches to analyses of mitochondrial phylogenies.The dispersal of anatomically modern humans from the African continent is examined through single nucleotide polymorphism (SNP) and sequence data. These data imply an expansion from Africa about 57 thousand years ago and a subsequent population dispersal into Asia. The dispersal coincides with a major population division that may be the result of multiple migratory routes to East Asia.Also investigated is the question of a common origin for the indigenous peoples of Australia and New Guinea. Previous studies have been equivocal on this question with some presenting evidence for a common genetic origin and other proposing separate histories. Our data reveals an ancient genetic link between Australian Aborigines and the peoples of the New Guinea highlands.

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Serrano, Érica Alves [UNESP]. "Origens dos cromossomos B em espécies de Characidium (Characiformes, Crenuchidae) baseada em pintura cromossômica, sequências de rDNA e histonas." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/108513.

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Made available in DSpace on 2014-08-13T14:50:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-27Bitstream added on 2014-08-13T18:00:59Z : No. of bitstreams: 1 000749628.pdf: 2138126 bytes, checksum: b934c7fd0a1cb3a925aa91c6b3804923 (MD5) Cromossomos B ou supranumerários são elementos extras ao conjunto padrão A e estão presentes em vários grupos de eucariotos, como plantas, fungos e animais. Podem ter origens distintas, incluindo derivação do conjunto autossômico ou de cromossomos sexuais e até mesmo por cruzamentos interespecíficos, o que os caracterizam como um interessante modelo para estudos genéticos e evolutivos. O advento da técnica de microdissecção cromossômica, método que possibilita o isolamento direto do DNA de qualquer região citogeneticamente reconhecida, tem proporcionado avanços no conhecimento da estrutura e composição destes elementos genômicos em um número significativo de organismos. Neste sentido, o presente trabalho foi desenvolvido com o objetivo de analisar os cromossomos B presentes em três espécies de peixes do gênero Characidium, através de técnicas citogenéticas clássicas e moleculares, envolvendo microdissecção dos cromossomos Bs e sexuais, associada à técnica de FISH, assim como hibridação fluorescente in situ dos DNAs ribossômicos 5S e 18S e DNAs histônicos H3 e H4. Adicionalmente, estas sequências de DNA repetitivo foram amplificadas, clonadas e sequenciadas a partir do DNA genômico de indivíduos sem cromossomos B e do DNA dos cromossomos B microdissecados. Os resultados obtidos pela pintura cromossômica confirmam que os cromossomos sexuais ZW possuem uma origem única neste grupo, enquanto os cromossomos B possuem dois tipos de origem. Em C. gomesi e C. pterostictum, os cromossomos B apresentam origem intraespecífica, relacionada aos cromossomos sexuais, mas independentes, considerando o posicionamento destas espécies na filogenia estabelecida. Por outro lado, em C. oiticicai esses elementos podem ter tido uma origem interespecífica, possivelmente relacionada a algum tipo de hibridação introgresiva. A presença de sequências histônicas e de DNAr 5S nos cromossomos B evidenciada pelo mapeamento ... B or supernumerary chromosomes are extra elements to the standard set A and are present in several groups of eukaryotes, such as plants, fungi and animals. They may have different origins, including derivation of autosomal or sex chromosomes and even by interspecific crosses, which make them as an interesting model for genetic and evolutionary studies. The advent of chromosome microdissection technique, a method that allows the direct isolation of DNA from any region cytogenetically recognized, has provided new information on the structure and composition of these genomic elements in a significant number of organisms. In this sense, the present work was developed aiming to analyze the B chromosomes present in three fish species of the genus Characidium through classical and molecular cytogenetic techniques involving microdissection of B and sex chromosomes associated with the FISH technique, as well as fluorescent in situ hybridization of 18S and 5S ribosomal DNAs and genes for the H3 and H4 histones. Additionally, these repetitive DNA sequences were amplified, cloned and sequenced from genomic DNA of individuals without B chromosomes and from B chromosomes DNA microdissected. The results obtained by chromosome painting confirmed that the ZW sex chromosomes have a single origin in this group, while the B chromosomes have two types of origin. In C. gomesi and C. pterostictum, B chromosomes apparently exhibit an intraspecific origin, related to sex chromosomes, but, considering the placement of these species in the phylogeny established, in independent events. Moreover, in C. oiticicai these elements might have had an interspecific origin, possibly related to some sort of hybridization by introgression. The presence of histone sequences and 5S rDNA in B chromosomes evidenced by physical mapping and PCR amplification, as well as low genetic divergence, indicate a common ancestry between sequences present in B chromosomes of C. gomesi ...

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Chilakamarri, Sunita R. "Genetic differentiation in Alewife populations using microsatellite loci." Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-053105-164623/.

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Bennett, Selester. "The construction and testing of maize transcriptional fusions in yeast (Saccharomyces cerevisiae)." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-10312009-020253/.

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Badenhorst, Daleen. "Development of AFLP markers for Haliotis midae for linkage mapping." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/21525.

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Thesis (MSc)--Stellenbosch University, 2008. ENGLISH ABSTRACT: Haliotis midae, is the only commercially important species of the six abalone species found in South African coastal waters and has become a lucrative commercial commodity. Wild stocks of H. midae are, however, no longer commercially sustainable due to a combination of environmental factors and poaching. The solution to the crisis is artificial production systems in the form of abalone farms. An abalone enhancement programme was initiated in South Africa in 2006, funded by industry and government. This programme focuses on the elucidation of the abalone genome and genetic factors contributing to increased productivity, thereby aiding the commercial production of abalone. The aims of this study, the first of its kind concerning H. midae, were to develop AFLPbased markers (specifically fluorescent AFLP analysis); to monitor the segregation of these markers in a single full-sib family and to use the markers and additional microsatellite markers to generate the first preliminary linkage map for H. midae. Genomic DNA of sufficient quality and purity for fluorescent AFLP analysis was obtained from 3.5-month-old H. midae juveniles. Preliminary linkage maps were constructed using AFLP and microsatellite markers segregating in an F1 family following a pseudo-testcross mapping strategy. Twelve AFLP primer combinations, producing 573 segregating peaks, and 10 microsatellite markers were genotyped in the parents and 108 progeny of the mapping family. Of the 573 segregating AFLP peaks genotyped, 241 segregated in a 1:1 ratio and 332 in a 3:1 ratio. Of these AFLP markers, 90 segregated according to the expected 1:1 Mendelian ratio and 164 segregated according to the expected 3:1 Mendelian ratio at the P = 0.05 level and were used for linkage analysis. Of the 10 microsatellite markers genotyped, nine were informative for linkage mapping analysis. Preliminary male and female genetic linkage maps were developed using markers segregating in the female or male parent. A total of 12 and 10 linkage groups were detected for the female and male maps respectively. The female map covered 1473.5cM and consisted of 56 markers, and the male map covered 738.9cM consisting of 30 markers. Markers with segregation distortion were observed as previously reported in other abalone species and potential homology between one of the linkage groups of the male map and two of the linkage groups of the female map were identified using the 3:1 segregating AFLP markers. In conclusion, the genetic linkage map presented here, despite the fact that it has relatively low genome coverage and low marker density, forms an ideal starting point for more detailed study of the H. midae genome and will provide a scaffold for basic and applied studies in abalone. A high-density linkage map of H. midae should in future be developed with additional co-dominant molecular markers, such as microsatellites, to improve the transferability of the linkage map between different laboratories and among populations. A high-density linkage map will facilitate the mapping of QTL of commercially important traits (i.e. growth) and future MAS breeding programmes. AFRIKAANSE OPSOMMING: Perlemoenspesie, Haliotis midae, is die enigste spesie van kommersiële belang van die ses wat in die kuswater van Suid-Afrika aangetref word en het ‘n winsgewende handelskommoditeit in Suid-Afrika geword. Die ontginning van natuurlike H. midae populasies is egter, as gevolg van ‘n kombinasie van omgewingsfaktore en stropery nie meer kommersieel volhoubaar nie. Die perlemoenkrisis kan die hoof gebied word deur kunsmatige produksiesisteme op perlemoenplase tot stand te bring. ‘n Perlemoen verbeteringsprogram is in 2006 in Suid-Afrika geïnisieer en word deur die industrie en regering befonds. Die program focus op die ontrafeling van die perlemoen genoom en die genetiese faktore wat bydrae tot verhoogde produksie. Sodanige inligting kan gebruik word om kommersiële perlemoenproduksie te bevorder. Die doel van hierdie studie, die eerste met H. midae, is om AFLP-gebaseerde merkers (spesifiek fluoresserende AFLP analise) te ontwikkel; die segregasie van hierdie merkers te monitor in ‘n enkel volledige verwante familie en die merkers en addisionele mikrosatelliet merkers te gebruik om die eerste voorlopige koppelingskaart vir H. midae te genereer. Genomiese DNS van genoegsame kwaliteit en suiwerheid vir fluoresserende AFLP analise is ge-ekstraeer uit 3.5-maand-oue H. midae individue. Voorlopige koppelingskaart is gekonstrueer deur van segregerende AFLP en mikrosatelliet merkers in ‘n F1 familie gebruik te maak deur ‘n pseudo-kruistoets karteringstrategie te volg. Twaalf AFLP inleier kombinasies, wat 573 segregerende fragmente geproduseer het, en 10 mikrosatelliet merkers is gegenotipeer in die ouers en 108 individue van die nageslag van die karteringsfamilie. Van die 573 segregerende AFLP merkers wat gegenotipeer is, het 241 in ‘n 1:1 verhouding en 332 in ‘n 3:1 verhouding gesegregeer. Van hierdie AFLP merkers, het 90 volgens die verwagte 1:1 Mendeliese verhouding en 164 volgens die 3:1 Mendeliese verhouding by die P = 0.05 gesegregeer vlak en is vir die koppelingsanalise gebruik. Van die 10 mikrosatelliet merkers gegenotipeer, was 9 informatief vir koppeling karteringsanalise. Voorlopige manlike en vroulike genetiese koppelingskaarte is ontwikkel met gebruik te maak van merkers wat in die manlike of vroulike ouer segregeer het. ‘n Totaal van 12 en 10 koppelingsgroepe is onderskeidelik in die vroulike en manlike karate gegenereer. Die vroulike kaart dek 1473.5cM and bestaan uit 56 merkers, terwyl die manlike kaart 738.9cM beslaan het met 30 merkers. Merkers wat segregasie distorsie toon is waargeneem soos voorheen in ander perlemoenspesies gerapporteer. Potensiële ooreenstemming tussen een van die koppelingsgroepe van die manlike kaart en twee van die koppelingsgroepe van die vroulike kaart is aangetoon deur van die 3:1 segregerende AFLP merkers gebruik te maak. Die genetiese koppelingskaarte verskaf wel ‘n relatiewe lae genoomdekking en ‘n lae merkerdigtheid, maar is ‘n ideale vertrekpunt vir meer gedetailleerde studie van die H. midae genoom en dien as ‘n raamwerk vir toekomstige basiese en toegepaste studies in perlemoennavorsing. ‘n Hoëdigtheid koppelingskaart van H. midae moet in die toekoms ontwikkel word met gebruik van bykomstige ko-dominante molekulêre merkers, soos mikrosatelliete. Dit sal die oordraagbaarheid van die koppelingskaart tussen verskillende laboratoria asook tussen populasies verbeter. ‘n Hoëdigtheid koppelingskaart sal die kartering van kwantitatiewe kenmerk loki (KKL) vir kommersieel belangrike kenmerke (onder andere groeikrag) en toekomstige merker bemiddelde seleksie (MBS) teelprogramme moontlik maak.

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26

Roxström-Lindquist, Katarina. "Innate Immunity in Insects, Function and Regulation of Hemolin from Hyalophora cecropia." Doctoral thesis, Stockholms universitet, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-3.

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Insects are useful models for the study of innate immune reactions and development. The distinction between recognition mechanisms preceding the breakdown of apoptotic cells during metamorphosis, and the breakdown of cells in response to infections, is unclear. Hemolin, a Lepidopteran member of the immunoglobulin superfamily, is a candidate molecule in self/nonself recognition. This thesis investigates hemolin function and hemolin gene regulation at a molecular level. We investigated the binding and cell adhesion properties of hemolin from H. cecropia and demonstrated that the proteins could homodimerize in presence of calcium. Moreover, a higher molecular weight membrane form of hemolin was present on hemocytes. These results, taken together with an earlier finding that soluble hemolin inhibits hemocyte adhesion, indicated that the secreted hemolin could modulate hemocyte aggregation in a competitive manner in the blood. In addition, hemolin was expressed in different tissues and at different developmental stages. Since hemolin is expressed both during development and during the immune response, its different regulatory factors must act in concert. We found that the third intron contains an enhancer, through which Dif, C/EBP and HMGI synergistically activate a reporter construct in vitro. We concluded that the enhancer is used during infection, since the κB-site is crucial for an immune response. Interestingly, we also found that the active form of the steroid hormone, ecdysone, induces the hemolin gene transcription in vivo, and in addition, acts synergistically during bacterial infection. Preliminary in vivo results indicate a secondary effect of ecdysone and the importance of hormone receptor elements in the upstream promoter region of hemolin. To explore the use of Drosophila as a genetic tool for understanding hemolin function and regulation, we sought to isolate the functional homologue in this species. A fly cDNA library in yeast was screened using H. cecropia hemolin as bait. The screen was not successful. However, it did lead to the discovery of a Drosophila protein with true binding specificity for hemolin. Subsequent characterization revealed a new, highly conserved gene, which we named yippee. Yippee is distantly related to zinc finger proteins and represents a novel family of proteins present in numerous eukaryotes, including fungi, plants and humans. Notably, when the Drosophila genome sequence was revealed, no hemolin orthologue could be detected. Finally, an extensive Drosophila genome chip analysis was initiated. The goal was to investigate the Drosophila immune response, and, in contrast to earlier studies of artificially injected flies, to examine a set of natural microbes, orally and externally applied. In parallel experiments viruses, bacteria, fungi and parasites were compared to unchallenged controls. We obtained a unique set of genes that were up-regulated in the response to the parasite Octosporea muscadomesticae and to the fungus Beauveria bassiana. We expect both down-regulated and up-regulated genes to serve as a source for the discovery of new effector molecules, in particular those that are active against parasites and fungi.

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27

Ahlgren, Berg Alexandra. "Developmental switches in a family of temperate phages." Doctoral thesis, Stockholm : Department of Genetics, Microbiology and Toxicology, Stockholm University, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-644.

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28

Bergman, Ingrid-Maria. "Polymorphism in pattern recognition receptor genes in pigs." Doctoral thesis, Linnéuniversitetet, Institutionen för naturvetenskap, NV, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-116.

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The mammalian immune defense consists of two systems, which are interconnected and co-operate to provide host defense. The innate immune system is always active and detects and responds to non-self without delay. The adaptive immune system has a lag phase, but is more specific and has got a memory. The innate immune system relies on pattern recognition receptors (PRRs) to detect molecular patterns signaling microbial presence. This thesis focuses on a centrally placed family of PRRs, namely the Toll-like receptors (TLRs), and on mannan-binding lectin (MBL), a PRR which initiates the lectin activation pathway of complement. TLRs are expressed on the cell surface and in intracellular compartments, while MBL is a soluble protein present in most body fluids. Polymorphism – literally ’many forms’ – refers to variation between individuals, at DNA level as well as in traits. A single nucleotide polymorphism (SNP) implicates that alternative nucleotides are present at a particular position in the genome. Mutations, together with phenomena like gene duplication and whole genome duplication, are the ultimate source of variation in nature and the fuel for evolution. Through natural selection and breeding, i.e. artificial selection, species are shaped and change over time. Domestic animals are well suited for genetic studies, since they enable comparisons of populations exposed to different selection criteria and environmental challenges. Also, in the case of pigs, comparisons to the wild ancestor – i.e. the wild boar – can shed light on the evolutionary process. Moreover, pigs are large animal models for humans. Paper I reports the refinement of previously identified quantitative trait loci for immune-related traits on pig chromosome 8. Papers II and III report differences in polymorphic patterns between wild boars and domestic pigs in the TLR1, TLR2, TLR6, and TLR10 genes. In TLR1 and TLR2, more SNPs were present in the domestic pigs than in the wild boars. In TLR6, SNP numbers were similar in both animal groups, but the level of heterozygosity was higher in the domestic pigs than in the wild boars. In TLR10, again, more SNPs were present in the domestic pigs, and a higher number of non-synonymous SNPs was detected in TLR10 compared to the other genes. This might suggest redundancy for TLR10 in pigs. Paper IV reports the presence of an SNP, previously detected in domestic pigs and assumed to affect MBL concentrations in serum, in European wild boars. Also, the connection between the presumed low-producing allele and low MBL concentration in serum was confirmed. Moreover, a novel SNP, with potential to be functionally important, was detected. Owing to the domestication process and differences in selection pressure, differences in polymorphic patterns between wild boars and domestic pigs are not surprising. However, since breeding means choosing among genotypes, the opposite pattern – more SNPs in wild boars than in domestic pigs – would have been expected. However, the result confirms other studies, which have shown that European wild boars went through a bottle neck before domestication started. The higher number of SNPs in domestic pigs may be due to relaxed purifying selection during the domestication process.

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Nordquist, Niklas. "Genetic Studies of Rheumatoid Arthritis using Animal Models." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2001. http://publications.uu.se/theses/91-554-5117-9/.

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30

Benson, Claire Elizabeth. "Genetics of familial hip osteoarthritis :identification of genetic susceptibility factors." Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491996.

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Osteoarthritis is already a major cause of disability worldwide and with an ageing population the associated socio-economic burden is expected to soar. Complex interactions between genetic and environmental factors are responsible for the initiation of osteoarthritis. There is a clear genetic contribution to hip' osteoarthritis but to date no major susceptibility gene has been identified. A large collection of affected sib pairs with hip osteoarthritis had already been recruited from Northern Ireland (416 participants) and Nottingham (115 participants) . Additional unaffected (n=42) family members were recruited. As part of a genome wide screen 160 microsatellite markers from chromosomes 9, 10, 11, 14, 19, 20, 21 and 22 were typed in each family member (n=531)and controls (n=49). Candidate genes were identified in areas suggesting positive linkage. Single nucleotide polymorphism (SNP) typing or sequencing were used to investigate these genes further. The three regions most suggestive of linkage were found in chromosomes 9 (at 74.4mB), 11 (at 11.7mB) and 19 (at 8mB). Ten of the candidate genes identified were typed with SNPs in one member of each family (n=206) and controls (n=49). The ten exons of the other gene, osteoclast stimulating factor 1 (OSTFl), were sequenced in both cases (n=40) and controls (n= 8). The only candidate gene with significantly positive results was the collagen type V, alpha 3 gene (COL5A3) on chromosome 19. One haplotype block was significantly more common in the control population (p=O.Ol). Further analyses of the COL5A3 gene and its neighbouring genes are currently underway. Identification of a major susceptibility gene will improve our understanding of the underlying pathogenesis and potentially identify new targets for drug therapy. The global impact of finding a major susceptibility gene for hip osteoarthritis should encourage us to continue with our search to elucidate the genetics of familial hip osteoarthritis

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31

Holmquist, Isabel Rosa. "A population genetics study of transposable elements as genetic drivers." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.516357.

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32

Qiao, Dandi. "Statistical Approaches for Next-Generation Sequencing Data." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10689.

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During the last two decades, genotyping technology has advanced rapidly, which enabled the tremendous success of genome-wide association studies (GWAS) in the search of disease susceptibility loci (DSLs). However, only a small fraction of the overall predicted heritability can be explained by the DSLs discovered. One possible explanation for this ”missing heritability” phenomenon is that many causal variants are rare. The recent development of high-throughput next-generation sequencing (NGS) technology provides the instrument to look closely at these rare variants with precision and efficiency. However, new approaches for both the storage and analysis of sequencing data are in imminent needs. In this thesis, we introduce three methods that could be utilized in the management and analysis of sequencing data. In Chapter 1, we propose a novel and simple algorithm for compressing sequencing data that leverages on the scarcity of rare variant data, which enables the storage and analysis of sequencing data efficiently in current hardware environment. We also provide a C++ implementation that supports direct and parallel loading of the compressed format without requiring extra time for decompression. Chapter 2 and 3 focus on the association analysis of sequencing data in population-based design. In Chapter 2, we present a statistical methodology that allows the identification of genetic outliers to obtain a genetically homogeneous subpopulation, which reduces the false positives due to population substructure. Our approach is computationally efficient that can be applied to all the genetic loci in the data and does not require pruning of variants in linkage disequilibrium (LD). In Chapter 3, we propose a general analysis framework in which thousands of genetic loci can be tested simultaneously for association with complex phenotypes. The approach is built on spatial-clustering methodology, assuming that genetic loci that are associated with the target phenotype cluster in certain genomic regions. In contrast to standard methodology for multi-loci analysis, which has focused on the dimension reduction of data, the proposed approach profits from the availability of large numbers of genetic loci. Thus it will be especially relevant for whole-genome sequencing studies which commonly record several thousand loci per gene.

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33

Lewis, Courtney. "Genetics Laboratory Directors’ Perspectives on the Role of Genetic Counselors in Acquired Mutation Testing: Current and Expanded Opportunities." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1396523134.

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34

Van, der Merwe Aletta Elizabeth. "Population genetic structure and demographical history of South African abalone, Haliotis midae, in a conservation context." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/3974.

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Thesis (PhD (Genetics))--University of Stellenbosch, 2009. ENGLISH ABSTRACT: South African abalone, Haliotis midae, has been the subject of major concern regarding its survival and conservation over the last decade or more. Being the only one of five endemic species with commercial value, there is considerable interest and urgency in genetic management and improvement of this species. Limited genetic information and the increasing conservation concern of this species are considered the key motivations for generating information on the micro- and macro-evolutionary processes of H. midae, the overall objective of this study. This study reported the first microsatellite and Single Nucleotide Polymorphism (SNP) markers developed specifically for Haliotis midae. Both these marker types were applied to elucidate the degree of gene flow in nine natural abalone populations whilst testing for two contrasting hypotheses; panmixia versus restricted gene flow. Data was analysed using a series of methodological approaches ranging from traditional summary statistics to more advanced MCMC based Bayesian clustering methods with and without including spatial information. Using only microsatellite data, the historical demography of the species was also examined in terms of effective population size and population size fluctuations. Finally, the evolutionary positioning and origin of Haliotis midae with regards to other Haliotis species was investigated based on mitochondrial and nuclear sequence data. Both microsatellite and SNP data gave evidence for subtle differentiation between West and East coast populations that correlates with a hydrogeographic barrier in the vicinity of Cape Agulhas. Population substructure was supported by AMOVA, FCA and Bayesian clustering analysis. Clustering utilizing spatial information further indicated clinal variation on both sides of the proposed barrier with a region in the middle coinciding with a secondary contact zone, indicating possible historical isolation during glacial periods. Overall, the similar degree of substructure observed with both microsatellites and SNPs supported the existence of contemporary and/or historical factors with genome-wide effect on gene flow. The population expansion measured with the microsatellites was inconsistent with the known recent decline but taking the species’ life cycle and large effective population size into account, a shrinkage in population size will probably only be apparent in a few generations time. On a macro-evolutionary scale, this study presents the first classification of South African abalone as a monophyletic group within the Haliotidae family. The topology based on the combined mitochondrial and nuclear dataset is highly suggestive of a relatively recent radiation of the SA species from the Indo-Pacific basin. The study concludes by describing the most likely factors that could have affected overall population structure and makes suggestions on how the given genetic information should be incorporated into strategies aimed towards the effective management and conservation of Haliotis midae. AFRIKAANSE OPSOMMING: Die Suid-Afrikaanse perlemoen, Haliotis midae, is oor die laaste dekade of meer die onderwerp van groot bekommernis betreffende die spesie se oorlewing en bewaring. Aangesien dit die enigste van vyf endemiese SA spesies is met kommersiёle waarde, is daar besonderse belang en erns in die genetiese beheer en verbetering van die spesie. Beperkte genetiese inligting en ‘n toenemende behoefte om die spesie te bewaar is die hoof motivering agter die generering van informasie rakende mikro- en makro-evolusionêre prosesse in Haliotis midae en is die oorhoofse doel van hierdie studie. Hierdie studie beskryf die eerste mikrosatelliete en enkel basispaar polimorfismes wat ontwikkel is spesifiek vir Haliotis midae. Beide tipe merkers is aangewend om die mate van gene vloei in nege wilde perlemoen populasies te ondersoek terwyl twee hipoteses ondersoek is; panmiksie versus beperkte gene vloei. Data is geanaliseer deur gebruik te maak van ‘n reeks metodieke benaderings wat wissel van tradisionele opsommings statistieke tot meer gevorderde MCMC gebasseerde groeperings metodes met of sonder die gebruik van geografiese data. Mikrosatelliet data is ook aangewend om die historiese demografie van die spesie te bepaal in terme van effektiewe populasie grootte asook veranderinge in populasie groottes. Laastens is die evolusionêre posisionering en oorsprong van Haliotis midae teenoor ander Haliotis spesies ondersoek deur gebruik te maak van mitokondriale en nukleêre DNA volgorde data. Beide mikrosatelliet en enkel basispaar polimorfisme data lewer bewys van ‘n subtiele genetiese verskil tussen wes en ooskus populasies wat verband hou met ‘n hidrografiese skeiding in die omgewing van Kaap Agulhas. Populasie struktuur is ondersteun deur die analise van molekulêre variansie (AMOVA), faktoriale komponente analise asook Bayesiese groeperings analise. Groeperings analise wat geografiese informasie insluit dui klinale genetiese variasie aan beide kante van die skeiding aan met ‘n area in die middel wat ooreenstem met ‘n sekondêre kontak gebied. In totaal, ondersteun die soortgelyke mate van struktuur verkry met beide die mikrosatelliete en enkel basispaar polimorfismes die bestaan van hedendaagse en/of historiese faktore met genoom wye invloed op gene vloei. Die toename in populasie grootte vasgestel deur die mikrosatelliet data stem nie ooreen met die onlangse afname waargeneem in die spesie nie, maar met inagneming van Haliotis midae se lewenssiklus en groot effektiewe populasie grootte, sal die afname in populasie grootte moontlik eers oor ‘n paar generasies na vore kom. Op ‘n makro-evolusionêre skaal lewer hierdie studie die eerste klassifikasie van Suid-Afrikaanse perlemoen as ‘n monofiletiese groep binne die Haliotidae familie. Die topologie gebaseer op ‘n gesamentlike mitkondriale en nukleêre datastel is hoogs aanduidend van ‘n relatiewe onlangse verspreiding van die Suid-Afrikaanse spesies uit die Stille-Indiese Oseaan. Die studie sluit af deur die mees algemene faktore te bespreek wat populasie struktuur kon beïnvloed het en maak voorstelle op watter wyse hierdie genetiese inligting aangewend kan word vir die effekiewe beheer en bewaring van Haliotis midae.

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35

Whitmore, Scott Anthony. "Positional cloning of genes associated with human disease /." Title page, contents and summary only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09phw616.pdf.

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Thesis (Ph.D.) -- University of Adelaide, Dept. of Cytogenetics and Molecular Genetics, 1999. Copies of author's previously published articles inserted. Amendments pasted onto back-end paper. Bibliography: leaves 255-286.

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36

Melville, Scott Andrew Biotechnology &amp Biomolecular Sciences Faculty of Science UNSW. "Disease gene mapping in border collie dogs." Awarded by:University of New South Wales. School of Biotechnology and Biomolecular Sciences, 2006. http://handle.unsw.edu.au/1959.4/25511.

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Pedigree dog breeds are genetically isolated and inbred populations with characteristics specific to each breed. Some breeds carry genetic diseases which affect the health of the animals, but may also serve as a valuable model to identify genes involved in human disease. In the Border Collie breed in Australia, the identification of two disease genes would enable breeders to DNA test their animals and prevent future cases. Over 530 samples were collected to identify the genes responsible for these diseases through linkage mapping and candidate gene approaches. Collie Eye Anomaly (CEA) defines a group of symptoms that cause the incorrect development of different regions within the eye, and may also result in the detachment of the retina. The presence of the disease in different breeds of collies suggests that the disease originated before the differentiation of the collie breeds. The CEA gene was mapped to a region of CFA37, but the disease gene was identified by another research group. Neuronal Ceroid Lipofuscinosis (NCL) is a fatal neurodegenerative disorder that affects Border Collie dogs from approximately 16 months of age. The disease is inherited in an autosomal recessive manner and affected animals display a range of physiological and behavioural symptoms that include loss of muscular control, nervousness and sometimes aggression. Due to the debilitating nature of the disease, dogs rarely survive beyond 28 months of age. Microsatellite markers were used to exclude the Border Collie NCL gene from the region of the English Setter NCL gene (homolog of human NCL gene CLN8). Further work mapped the disease gene to CFA22, in a region containing the homolog for CLN5, one of the identified human disease genes for NCL. Subsequent sequencing of canine CLN5 revealed a nonsense mutation (c.619C>T, Q206X) that co-segregated with NCL in Border Collie pedigrees. This truncation mutation resulted in a protein product of similar size to some mutations identified in human CLN5 and therefore the Border Collie may make a good model for future NCL studies. With DNA testing now available, breeders of Border Collies can now ensure that no animal will die of NCL.

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Gress, Leslie Anne. "Adult Use of Longitudinal Genetic Services." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1336507935.

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Muller, Reka D. "Evaluation of Clinical Practices and Needs about Variants of Uncertain Significance Results in Inherited Cardiac Arrhythmia and Inherited Cardiomyopathy Genes." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7863.

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The increasing numbers of genetic tests in clinical settings have identified many variants of uncertain significance (VUS) in genes associated with inherited cardiac arrhythmias and inherited cardiomyopathies. Evaluation of clinical practices including counseling strategies and medical management recommendations for patients and their families is important to improve patient outcomes and prevent over- or under-treatment that may result in morbidity or fatality. The purpose of this study is to describe provider practices related to VUS results including how they conduct risk assessments and ascertain what information and medical management recommendations they provide to patients with VUS results and the patients’ family members. Additionally, we aim to describe providers’ concerns and informational needs related to counseling about a VUS. An anonymous online survey was developed for the current study and distributed to genetic counselors through the National Society of Genetic Counselors (NSGC) listerv and to cardiologists via emails obtained from publicly available resources. The survey explored healthcare providers’ confidence in counseling about a VUS, explanation of a VUS to patients, topics covered before and after genetic testing, and recommendations for patients with a VUS and their families using clinical vignettes. Providers (N=102) who completed the survey included 29 cardiovascular genetic counselors, 50 genetic counselors from other specialties, and 23 cardiologists. A hypothetical clinical scenario was used in which a young adult patient had a VUS in a gene causing Arrhythmogenic Right Ventricular Cardiomyopathy, but did not meet clinical diagnostic criteria for the condition. The patient’s only concerning issues included a personal history of fainting during exercising and sudden death of a 45 year old first-degree relative. Nearly 9% of all providers incorrectly described the VUS as likely pathogenic, while 15% would downplay the finding by indicating the VUS is more likely to eventually be reclassified as benign. Genetic counselors feel more confident about counseling about VUS results (p<0.001). Both cardiovascular genetic counselors and cardiologists feel confident in making medical management recommendations; however, cardiologists are more likely to recommend treatment with beta-blockers and exercise limitation for the patient. Compared to cardiac genetic counselors, other genetic counselors (p=0.001) and cardiologists (p=0.014) were more likely to recommend clinical testing for family members even though testing is expected to be uninformative, especially given the absence of any clinical diagnosis in the family. These findings highlight the expertise of different providers in different specialty area and suggest the need for interdisciplinary clinics that include cardiologists, cardiac genetic counselors, nurses, geneticists, psychologists and others to optimize care for challenging cases where VUS results create uncertainty.

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39

Campino, Susana. "Genetic analysis of murine malaria." Doctoral thesis, Umeå universitet, Medicinsk biovetenskap, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-124.

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Malaria, an infectious disease caused by Plasmodium parasites, is one of the major world-scale health problems. Despite the efforts aimed at finding an effective way to control the disease, the success has been thwarted by the emergence of parasite drug resistance and mosquito resistance to insecticides. This thesis focuses on the genetic analysis of resistance to murine malaria induced by the lethal Plasmodium berghei ANKA using a wild-derived-inbred strain (WDIS). The aim of this thesis was to exploit the genetic diversity represented among WDIS for identifying loci contributing to resistance/susceptibility to murine malaria. The work included a genome-wide polymorphism survey using microsatellite markers performed on 10 WDIS. Comparisons of these strains to laboratory inbred strains confirmed a higher rate of polymorphism among the WDIS. We conclude that these WDIS represent repositories of unique naturally occurring genetic variability that may prove to be invaluable for the study of complex phenotypes. Next, we used the WDIS to search for novel phenotypes related to malaria pathogenesis. Whereas most laboratory strains were susceptible to experimental cerebral malaria (ECM) after infection with P. berghei ANKA, several WDIS were found to be resistant. To study the genetic inheritance of resistant/susceptibility to P. berghei ANKA infection we analysed backcross and F2 cohorts derived from crossing the WLA wild-derived strain with a laboratory mouse strain (C57BL/6). A novel phenotype represented by the cure of infection, clearance of parasitaemia and establishment of immunological memory was observed in the F2 progeny. The backcross progeny was used to genetically map one locus on chromosome 1 (Berr1) and one locus on chromosome 11 (Berr2) that mediate control of resistance to ECM induced by P. berghei ANKA. Genetic mapping using the F2 progeny showed that a locus on chromosome 1 (Berr1) and a locus on chromosome 9 (Berr3) were contributing to control survival time after infection with lethal Plasmodium. Finally, we identified, a locus on chromosome 4 (Berr4) that appears to control time of death due to hyperparasitaemia. This thesis underlines the value of using WDIS to reveal genetic factors involved in the aetiology of disease phenotypes. The characterisation of the genetic factors represented by the malaria resistance loci identified here are expected to provide a better understanding of the malaria pathology.

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Goldstein, Ellen Sara. "Estimating the Incidence of Germline Mutations in Patients with Bone and Soft Tissue Sarcoma using Clinical Tumor Sequencing." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1592844958063832.

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Reodica, Mayfebelle Biotechnology &amp Biomolecular Sciences Faculty of Science UNSW. "Transcriptional repression mechanisms of sporulation-specific genes in saccharomyces cerevisiae." Awarded by:University of New South Wales. School of Biotechnology and Biomolecular Sciences, 2006. http://handle.unsw.edu.au/1959.4/32731.

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For organisms undergoing a developmental process it is ideal that specific genes are induced and repressed at the correct time and to the correct level in a coordinated manner. The process of meiosis and spore formation (collectively known as sporulation) in Saccharomyces cerevisiae provides a convenient system to elucidate transcriptional mechanisms of gene repression and the contribution such repression mechanisms offer to cells capable of undergoing a developmental process. This thesis focuses on transcriptional repression of sporulation-specific genes during both vegetative/mitotic conditions and sporulation. The fitness contribution of transcriptional repressors that regulate sporulationspecific genes during vegetative growth were investigated considering the similarities between meiosis and mitosis such as DNA replication, chromosome segregation and cytokinesis. Well-characterised sporulation genes of different functions were expressed in vegetative cells and ectopic expression of these genes was found not to be lethal. It was ascertained through strain competition studies that ectopic expression of the genes IME1, SMK1, SPR3 and DIT1 during mitotic growth did not affect cellular fitness. The expression of NDT80 in vegetative cells, however, caused a marked reduction in fitness and cells were also further compromised in the absence of the Sum1p repressor that regulates NDT80 transcription. The role of NDT80 as a transcriptional activator of middle sporulation genes, rather than the over-expression of NDT80 as a protein, caused the reduction of cell viability. Transcriptional regulation of the middle sporulation-specific gene SPR3 by the meiosis-specific Set3p repressor complex was investigated using synchronous sporulation cultures of the W303a/?? strain commonly used for sporulation studies. In a mutant W303a/?? ??set3/??set3 strain, lacking a key component of the Set3p repression complex, the transcription of SPR3 was uncharacteristically expressed at higher levels and derepressed during late sporulation. This SPR3 expression was consistent for both SPR3 transcript and SPR3::lacZ reporter protein studies. This preliminary work will enable future studies, using SPR3 promoter deletions fused to a lacZ reporter, aimed at determining the region of the SPR3 promoter that the Set3p complex may interact with to transcriptionally repress the gene during sporulation.

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Ingvoldstad, Charlotta. "Barnmorskors upplevelse av att förmedla information och ge vägledning om genetik och fosterdiagnostik till blivande föräldrar." Thesis, Uppsala universitet, Institutionen för folkhälso- och vårdvetenskap, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-230902.

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Inledning: I Sverige har alla blivande föräldrar rätt till fri mödravård. I stort sett alla kvinnor utnyttjar den förmånen. Barnmorskor vid MVC är ofta den första kontakten som de blivande föräldrarna träffar under graviditeten, och har också huvudansvaret för graviditeten ända fram till barnets födelse. Under de senare åren har mödravården alltmer fokuserat på det ofödda barnets hälsa. Förutom de rutinmässiga undersökningarna och samtalen är barnmorskans uppgift också att ge information kring olika fosterdiagnostiska metoder och genetiska avvikelser som kan upptäckas. Utifrån informationen ska de blivande föräldrarna kunna fatta egna beslut kring fosterdiagnostik, och ofta ta ett snabbt beslut. Det är därför viktigt att den information som ges är tydlig och detaljerad. Barnmorskans information ska göra att man känner sig trygg med de beslut man tar. Den utökade kunskapen, medvetenheten och känsligare tekniken ökar den enskilda förälderns önskan om relevant information och därför ställs högre krav på barnmorskor i rollen som förmedlare av information kring genetik och fosterdiagnostik. Därför är det viktigt att undersöka hur barnmorskorna själva upplever sin kunskapsnivå inom dessa områden, om de själva anser sig ha fått tillräcklig utbildning för att ge denna information till de blivande föräldrarna. Syftet med studien var att undersöka hur barnmorskor upplever sin kunskapsnivå och utbildning inom fosterdiagnostik och genetik samt att undersöka vilka behov för utökade resurser inom dessa ämnen barnmorskorna ansågs föreligga. Material och metod: Totalt 200 barnmorskor på MVC, fördelade mellan olika regioner av Sverige, deltog i en enkätundersökning våren 2005. Svarsutfallet var 30 %. Frågeformuläret innehöll 49 frågor med både fasta och öppna svarsalternativ. Formuläret var bearbetat och utformat för denna studie. Resultat: Majoriteten av barnmorskorna ansåg sig ha bristfällig kunskap inom fosterdiagnostik och genetik. Många barnmorskor ansåg sig ha lite, men ej tillräcklig, kunskap kring ultraljud och moderkaks- och fostervattenprov. En fjärdedel av barnmorskorna ansåg sig inte ha någon kunskap alls kring NUPP eller genetik. Barnmorskorna ansåg också att de har fått för lite eller ingen utbildning alls inom dessa områden. Så stor andel som 67 % önskar ytterligare utbildning inom ovanstående ämnen. En liten andel (6 %) anser att det vore bra om några få barnmorskor fick ytterligare utbildning och på så sätt få en ökad kompetens. 11 % av barnmorskor ansåg att det vore bra med personer med specialkompetens, genetiska vägledare, knutna till mödravården, som de kan hänvisa blivande föräldrar till. Konklusion: Denna studie har resulterat i en sammanställning av hur de tillfrågade barnmorskorna vid MVC själva uppfattar sin kompetens och utbildning inom genetik och fosterdiagnostik. Då barnmorskorna själva ansåg sig ha bristfällig kunskap inom fosterdiagnostik och genetik samt ansåg att de fått för lite utbildning inom dessa ämnen bör tillvägagångssättet för genetisk vägledning vid svensk mödravård ses över. Resultaten från denna studie kan ses som ett viktigt underlag för hur genetisk vägledning för blivande föräldrar kan förbättras i Sverige. Introduction: In Sweden, all pregnant women have the right and access to free antenatal care. A midwife is often the first professional contact the expecting parents will encounter, and the midwife is also the person with the key responsibility for the pregnancy. In recent years, antenatal care has increasingly focussed on the health of the unborn child. In addition to routine examinations and conversation, the midwives role is to inform about prenatal diagnosis, the risk figures, and the genetic divergence that can be detected. The parents should, based on this information, be able to make a decision about prenatal diagosis. It is therefore crucial that the information conveyed is clear and sufficient. As the knowledge and awareness in this area increases and as thetechniques gets more accurate, parents desire more relevant information, and the demand on midwives as informers in this area increases proportionally. Therefore it is important to investigate how the midwives experience their own knowledge about prenatal diagnosis and genetics, and if they consider that they have sufficient education in this area. Aims of the study: to investigate how midwives experience their own knowledge about prenatal diagnosis and genetics, to investigate if they consider that they have sufficient education in this area and to investigate what kind of needs for increased resources within this area the midwivesconsider to be important. Material and method: In total 200 antenatal care midwives from various towns of different sizes and from various regions throughout Sweden were invited to take part in a survey in the course of spring 2005. A questionnaire containing 49 questions was distributed by e- mail. About 30 % of the questionnaires were answered and returned. This questionairre was designed for this study. Results:Most midwives considered that they had insufficient knowledge about prenatal diagnosis and genetics. Many midwives said that they had some, but insufficient knowledge about ultrasound and chorionic villus sampling and amniocentesis. As many as 25% of the midwives thought that they had no knowledge about NUPP and genetics. The midwives also considered that they had none or only little education in prenatal diagnosis and genetics. Most midwives (67 %) answered that they would like additional education within prenatal diagnosis and genetics. A few (6 %) think it would be valuable if a few midwives could get extra education and thus increased competence. Others (11 %) consider it a good idea to employ genetic councellors within antenatal care. Conclusion: This study shows how midwives within antenatal care in Sweden assess their own knowledge and education within genetics and prenatal diagnosis. As the midwives consider that they have insufficient knowledge and education in this area, the way of giving this kind of information and genetic councelling within antenatal care in Sweden should be investigated.The results from this study can be regarded as a basis of how geneic councelling for expecting parents could be improved in Sweden.

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Dalenius, Jenny. "Domestication and coat colours : A review." Thesis, Linköpings universitet, Biologi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-176672.

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The domestication of animals is a process of great interest to many scientific fields, including genetics. Differences in coat colour between wild and domesticated animals have been of scientific interest for a long time. Coat colours are easily recognizable phenotypes and so have been studied since the dawn of modern genetics. Many phenotypes that are similar across species have the same genetic basis, but there are numerous exceptions. Similar phenotypes within a species can also have different genetic backgrounds. The progressive advances in genetic research methodology have given new insights into both the molecular basis for coat colours and the history of domestication over the last decades. The variation in coat colours seen today is believed to be caused mainly by human selection. Similarities in morphological changes between different species during domestication, including colour phenotypes such as white spotting, have long been noted. This is known as the domestication syndrome and two major hypotheses for this have been suggested: the neural crest hypothesis and the thyroid hormone hypothesis. This thesis gives an overview of the current knowledge about the genetic basis of coat colours in mammals, the genetic aspects of domestication of animals, and how the two are related.

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Balciuniene, Jorune. "Genetic studies of two inherited human phenotypes : Hearing loss and monoamine oxidase activity." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2001. http://publications.uu.se/theses/91-554-4917-4/.

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Sene, Viviani França [UNESP]. "Citogenética molecular e caracterização cromossômica no gênero Eigenmannia (Teleostei, Gymnotiformes, Sternopygidae)." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/99394.

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Made available in DSpace on 2014-06-11T19:30:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-29Bitstream added on 2014-06-13T20:39:50Z : No. of bitstreams: 1 sene_vf_me_botib.pdf: 1250166 bytes, checksum: ef91b80ce3068f6731dda41593edae4e (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Foram analisadas seis espécies/citótipos de peixes do gênero Eigenmannia, Eigenmannia sp1, Eigenmannia sp2, E. cf. trilineata, Eigenmannia sp e dois citótipos de E. virescens de diferentes bacias hidrográficas brasileiras, com o uso de técnicas citogenéticas básicas (coloração com Giemsa, localização das RONs pela marcação com nitrato de Prata e bandamento C) e moleculares (hibridação fluorescente in situ com sondas de DNAr 18S e 5S, com sondas teloméricas (TTAGGG)n, com sondas para elementos retrotransponíveis Rex 1 e Rex 3 e também por microdissecção, amplificação e hibridação in situ fluorescente com sonda produzida a partir do cromossomo sexual Y de Eigenmannia sp2). As espécies/citótipos analisados apresentaram intensa variação em seus números diploides, de 2n=28 cromossomos em Eigenmannia sp1, 2n=31/32 em Eigenmannia sp2, 2n=34 em E. cf. trilineata, 2n=36 em Eigenmannia sp e 2n=38 em E. virescens, além da ocorrência de sistema sexual XX-XY no citótipo de E. virescens do rio Ribeirão Claro (chamado de E. virescens-XY) e ausência desse sistema no citótipo do rio Mogi-Guaçu (chamado de E. virescens), bem como a ocorrência de sistema múltiplo do tipo X1X1X2X2-X1X2Y em Eigenmannia sp2 do rio Araquá. O DNAr 5S está organizado em duas classes distintas e foi localizado em diferentes cromossomos entre estas espécies/citótipos, mas sempre em posição terminal dos cromossomos, com exceção apenas do par cromossômico 7 de Eigenmannia sp1, que possui DNAr 5S em posição intersticial. Ainda, sequências de DNAr 5S foram localizadas no par sexual XY do citótipo de E. virescens-XY, evidenciando uma nova característica dos cromossomos sexuais deste grupo. As RONs, identificadas pelo tratamento com nitrato de Prata e pela sonda de DNAr 18S, foram sempre localizadas em compartimentos cromossômicos distintos do DNAr 5S e, apesar de serem localizadas... Conventional (Giemsa, Ag-NOR, C-banding) and molecular (Fluorescent in situ hybridization with 18S and 5S rDNA probes, telomeric repeats (TTAGGG)n, Rex1 and Rex3 retrotransposable elements and microdissection, amplification and fluorescent in situ hybridization with probes produced from the Y sex chromosome of Eigenmannia sp2.) cytogenetic studies were carried out in six fish species/cytotypes of the genus Eigenmannia from different Brazilian hydrographic basins. The analyzed species/cytotypes presented an intense variation in diploid number, ranging from 2n=28 chromosomes in Eigenmannia sp1, 2n=31/32 in Eigenmannia sp2, 2n=34 in Eigenmannia cf. trilineata, 2n=36 in Eigenmannia sp to 2n=38 in E. virescens, besides the occurrence of a sex chromosome system XX-XY in the cytotypes of E. virescens from Ribeirão Claro river (named as E. virescens-XY) and absence of this sex chromosome system in the cytotypes of Mogi-Guaçu river (named E. virescens), as well as the occurrence of a multiple sex chromosome system X1X1X2X2-X1X2Y in Eigenmannia sp2 from Araquá river. The 5S rDNA is organized in two distinct classes and was located in different chromosomes between these species/cytotypes; on the other hand, the location in the terminal position of chromosomes was a conserved feature, with exception of chromosome pair 7 in Eigenmannia sp1, which had 5S rDNA sites in an interstitial position. Yet, 5S rDNA signals were detected on the XY sex chromosome of E. virescens-XY, showing some new characteristics of sex chromosomes in this group. The NORs, identified by silver nitrate staining and 18S rDNA probes, were always located in distinct chromosome compartments of 5S rDNA and besides located in different chromosomes in all analyzed samples, they remained conserved through the karyotypic differentiation process in this group. The analysis of constitutive heterochromatin... (Complete abstract click electronic access below)

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Robertson, Michael Paul. "Engineered regulation of an RNA ligase ribozyme." Access restricted to users with UT Austin EID Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3035968.

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Singh, Nagendra Kumar. "The structure and genetic control of endosperm proteins in wheat and rye." Title page, contents and abstract only, 1985. http://web4.library.adelaide.edu.au/theses/09PH/09phs6174.pdf.

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Agarwala, Vineeta. "Integrating empirical data and population genetic simulations to study the genetic architecture of type 2 diabetes." Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:11120.

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Most common diseases have substantial heritable components but are characterized by complex inheritance patterns implicating numerous genetic and environmental factors. A longstanding goal of human genetics research is to delineate the genetic architecture of these traits - the number, frequencies, and effect sizes of disease-causing alleles - to inform mapping studies, elucidate mechanisms of disease, and guide development of targeted clinical therapies and diagnostics. Although vast empirical genetic data has now been collected for common diseases, different and contradictory hypotheses have been advocated about features of genetic architecture (e.g., the contribution of rare vs. common variants). Here, we present a framework which combines multiple empirical datasets and simulation studies to enable systematic testing of hypotheses about both global and locus-specific complex trait architecture. We apply this to type 2 diabetes (T2D).

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Myers, Katherine Joyce. "Acceptability and Familiarity of Genetic Treatment Technologies: A Survey of Individuals with Sudden Arrhythmia Death Syndrome (SADS) Conditions." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1554993385165476.

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Silva, Patrícia Kaliny Andrade da [UNESP]. "Estimativas de parâmetros genéticos para características de habilidade materna e reprodutivas em fêmeas da raça Santa Inês." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/115712.

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Made available in DSpace on 2015-03-03T11:52:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-03-12Bitstream added on 2015-03-03T12:06:39Z : No. of bitstreams: 1 000810103.pdf: 254757 bytes, checksum: 3e9716f53c787d573689cbd89abd14c6 (MD5) O objetivo geral do trabalho foi estimar parâmetros genéticos para características de habilidade materna: relação de desmame (REL), peso total das crias ao nascer e ao desmame (PTCN e PTCD) e reprodutivas: intervalo entre partos (IEP), idade ao primeiro parto (IPP), número de cordeiros por parto (NCP) para uma população de ovinos Santa Inês do Nordeste do Brasil e propor estratégias para seleção de reprodutores e fêmeas na raça baseado nos parâmetros genéticos estimados para as características em estudo. Foram utilizados dados pertencentes à Associação Sergipana dos Criadores de Caprinos e Ovinos (ASCCO) da raça Santa Inês. Os registros foram coletados entre 2003 e 2011 e continham informações de 4792 matrizes e 11575 nascimentos de 45 propriedades. Com o auxílio do software R foram realizadas as análises de consistência dos dados e foram testados os efeitos de ambiente para verificar seus efeitos nas características avaliadas com o objetivo de fornecer subsídio à formação dos grupos de contemporâneos. A idade da matriz ao parto foi considerada como covariável e ambos os efeitos (grupos contemporâneos e a covariável) foram considerados como efeitos fixos nos modelos de avaliação genética. Os efeitos aleatórios considerados foram: os efeitos genéticos aditivo direto (a), genético materno (m) e de ambiente permanente do animal (p). As estimativas de (co)variância para as características foram obtidas por máxima verossimilhança restrita e para a estimação foi usado o software WOMBAT e o algoritmo escolhido foi o PXEM para as análises multicaracterísticas que foram realizadas sob o modelo animal. As herdabilidades genéticas aditivas estimadas para as características reprodutivas e de habilidade materna foram de baixa magnitude IEP (0,02), NCP (0,10), REL(0,18), PTCN(0,10), com exceção de IPP (0,24) e PTCD (0,30), que apresentaram herdabilidade de magnitude ... The objectives of this study are to estimate genetic parameters for traits of maternal ability: weaning rate (REL), total weight of the offspring at birth and at weaning (PTCN and PTCD, respectively); and reproductive traits: calving interval (IEP), age at first calving (IPP), number of lambs per birth (NCP) for a population of Santa Inês sheep in Northeastern Brazil; and propose strategies for breed selection of sires and dams. The dataset of Santa Inês breed was obtained from Associação Sergipana dos Criadores de Caprinos e Ovinos (ASCCO). Data were collected between 2003 and 2011 and contained information of 4792 dams and 11575 births of 45 properties. The software R was used for data consistency and for testing the effects of environment on the characteristics just described to establish criteria to form contemporary groups. The dam age at birth was included as covariate, and both effects (contemporary group and covariate) were considered as fixed effects in the models for genetic evaluation. Moreover, the model included random effects, such as: direct- genetic additive (a), direct-maternal genetic (m), and common environment (p). Estimates of (co) variance for the traits were obtained by restricted maximum likelihood by using WOMBAT software, and the chosen algorithm was the PXEM for multi-trait animal model. The estimated genetic-additive heritability presented low magnitude for characteristics, such as: IEP (0,02), NCP (0,10), REL(0,18), and PTCN(0,10), with the exception of IPP (0,24) and PTCD (0,30) that showed heritability of moderate magnitude. The heritability for the maternal effect was low for all characteristics evaluated: PTCN (0,08), PTCD(0,5), REL (0,05) e NCP (0,14). High favorable genetic correlations were observed for PTCD and PTCN (0,96), and PTCD and NCP (0,69), whereas high unfavorable genetic correlations were observed between NCP and IPP (0,96). After evaluating ...

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Dissertations / Theses on the topic 'Genetics'

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