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Parts, Leopold. "Genetic mapping of cellular traits." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609665.
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Melville, Scott Andrew Biotechnology & 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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Einarsdottir, Elisabet. "Mapping genetic diseases in northern Sweden." Doctoral thesis, Umeå universitet, Medicinsk biovetenskap, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-499.
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The population of northern Sweden has previously been shown to be well suited for the mapping of monogenic diseases. In this thesis we have tested the hypothesis that this population could also be used for efficient identification of risk genes for common diseases. In Paper I we have hypothesised that despite the admixture of Swedish, Finnish and Sami, the northern Swedish population consists of sub-populations geographically restricted by the main river valleys running through the region. This geographic isolation, in combination with founder effects and genetic drift, could represent a unique resource for genetic studies. On the other hand, it also underlines the importance of accounting for this e.g. in genetic association studies. To test this hypothesis, we studied the patterns of marriage within and between river valley regions and compared allelic frequencies of genetic markers between these regions. The tendency to find a spouse and live in the river valley where one was born is strong, and allelic frequencies of genetic markers vary significantly between adjacent regions. These data support our hypothesis that the river valleys are home to distinct sub-populations and that this is likely to affect mapping of genetic diseases in these populations. In Paper II, we tested the applicability of the population in mapping HSAN V, a monogenic disease. This disease was identified in only three consanguineous individuals suffering from a severe loss of deep pain perception and an impaired perception of heat. A genome-wide scan combined with sequencing of candidate genes resulted in the identification of a causative point mutation in the nerve growth factor beta (NGFB) gene. In Paper III, a large family with multiple members affected by familial forms of type 1 diabetes mellitus (T1DM) and autoimmune thyroiditis (AITD) was studied. This syndrome was mapped to the IDDM12 region on 2q33, giving positive lodscores when conditioning on HLA haplotype. The linkage to HLA and to the IDDM12 region thus confirmed previous reports of linkage and/or association of T1DM and AITD to these loci and provided evidence that the same genetic factors may be mediating these diseases. This also supported the feasibility of mapping complex diseases in northern Sweden by the use of familial forms of these diseases. In Paper IV, we applied the same approach to study type 2 diabetes mellitus (T2DM). A non-parametric genome-wide scan was carried out on a family material from northern Sweden, and linkage was found to the calpain-10 locus, a previously described T2DM-susceptibility gene on 2q37. Together, these findings demonstrate that selecting for familial forms of even complex diseases, and choosing families from the same geographical region can efficiently reduce the genetic heterogeneity of the disease and facilitate the identification of risk genes for the disease.
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Einarsdóttir, Elísabet. "Mapping genetic diseases in northern Sweden." Umeå : Department of Medical Biosciences, Umeå University, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-499.
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MacGregor, Stuart. "Genetic linkage mapping in complex pedigrees." Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/12507.
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Genetic linkage analysis is the primary method for the identification of loci contributing to complex disease susceptibility. Linkage analysis techniques can be applied to both disease status (discrete traits) and to quantitative trait measures (quantitative trait loci or QTL mapping). Such techniques will be most effective if they can be applied to all of the available data; in human, ecological and livestock genetics this often means families with complex pedigree structures. The analysis of complex pedigrees is more difficult, both in terms of model formulation and computational ease, than similar studies of small family structures such as affected sibling pairs (ASP). Univariate variance component (VC) techniques suitable for QTL analysis of both quantitative and qualitative (via a threshold model) traits are described. Extensions to the univariate VC methods are proposed, allowing QTL analyses of longitudinal data in complex pedigrees, with polynomial based covariance functions offering a parsimonious description of the covariance structure across measures. Computer simulations are used to show that, under a range of realistic scenarios, the longitudinal QTL method offers more power to detect QTL than univariate or repeated measures methods. The longitudinal method is subsequently applied to a 330 extended families from the Framingham Heart Study, allowing the identification of QTL for a number of cardiovascular disease risk factors. The maximum LOD score (3.12) is obtained on chromosome 16 for Body Mass Index (BMI) and subsequent multivariate analyses showed that this QTL is most relevant to BMI at early ages. Threshold model based VC and parametric linkage analyses are applied to a set of Scottish families affected by psychiatric disease. The results from this analysis are in agreement with previous results implicating chromosome 1q42 in psychiatric disease susceptibility. The broad application of the VC techniques is further demonstrated by applying the techniques to a QTL mapping problem in a very large Red Deer (Cervus Elaphus) pedigree.
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Johanneson, Bo. "Genetic Mapping of Susceptibility Genes for Systemic Lupus Erythematosus." Doctoral thesis, Uppsala University, Department of Genetics and Pathology, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-2950.
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Systemic lupus erythematosus (SLE) is a complex autoimmune disease with unknown etiology. The aim of this thesis was to identify susceptibility regions through genetic mapping, using model-based linkage analysis on nuclear and extended SLE multicase families.
In the first paper we performed a genome scan on 19 genetically homogenous Icelandic and Swedish families. One region at 2q37 was identified with a significant linkage with contribution from both populations (Z=4.24). Five other regions 2q11, 4p13, 9p22, 9p13 and 9q13 showed suggestive linkage (Z>2.0).
In the second paper, 87 families from 10 different countries were analysed only for chromosome 1. One region at 1q31 showed significant linkage (Z=3.79) with contribution from families from all populations, including Mexicans and Europeans. Four other regions 1p36, 1p21, 1q23, and 1q25, showed levels of suggestive linkage. Linkage for most regions was highly dependent on what population was used, which indicated strong genetic heterogeneity in the genetic susceptibility for SLE.
In the two last papers, we used the positional candidate gene strategy, in order to investigate candidate genes in two regions linked to SLE. For the Bcl-2 gene (at 18q21) we could not detect any association with SLE using three different markers. However, when we investigated the tightly linked low-affinity family of FcγR genes (at 1q23), we could find association for two risk alleles in the FcγRIIA and FcγRIIIA genes. The risk alleles were transmitted to SLE patients on one specific haplotype and therefore are not independent risk alleles.
The results show that model-based linkage analysis is a strong approach in the search for susceptibility genes behind complex diseases like SLE.
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Guo, Youling, and 郭友玲. "Genetic and genomic mapping of common diseases." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B50533861.
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Genome-wide mapping of susceptibility genes was conducted in two complex disorders of hypertension and epilepsy, allowing the dissection of the genetic architecture of these common diseases and related quantitative traits. The study performed comprehensive genetic analyses in a genome-wide scale, using different structure of data – sib-pairs and case-control samples.
To identify genes influencing hypertension and blood pressure, a combined linkage and association study was conducted using over half a million SNPs genotyped in 328 siblings. Regions of significant linkage were identified for blood pressure traits on chromosomes 2q22.3 and 5p13.2, respectively. Further family-based association analysis of the linkage peak on chromosome 5 yielded a significant association (rs1605685, P < 7 10-5) for hypertension. One candidate gene, PDC, was replicated in the family-based association tests.
A two-stage genome-wide association study (GWAS) was performed in a total of 1,087 cases and 3,444 controls, to identify common susceptibility variants of epilepsy in Chinese. The combined analysis identified two association signals in CAMSAP1L1, rs2292096 [G] (P=1.0×10-8, OR =0.63) and rs6660197 [T] (P=9.9×10-7, OR=0.69), which are highly correlated, achieving genome-wide significance. One SNP (rs9390754, P = 1.7 × 10-5) in GRIK2 was refined as a previously-implicated association. In addition to SNPs, the assessment of CNVs in GWAS was performed, which could provide valuable clues to discover genes contributing to the heritability of epilepsy. A genome-wide scan for epilepsy through the use of DNA pooling also provides an alternative approach to reducing the substantial cost and thus increase efficiency in large-scale genetic association studies.
The genome-wide mapping studies in families and unrelated individuals are complementary and together offer a comprehensive catalog of common variations and structural variants implicated for both quantitative and qualitative traits.published_or_final_version
Psychiatry
Doctoral
Doctor of Philosophy
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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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Moody, Adrian John. "Mapping genetic resistance to infectious bursal disease." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326754.
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Duran, Alonso Maria Beatriz. "Genetic mapping of the rat agu gene." Thesis, University of Glasgow, 1997. http://theses.gla.ac.uk/39021/.
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In 1993, a mutant strain, AS/AGU arose spontaneously in an enclosed colony of the Albino Swiss (AS) strain of rat. AS/AGU animals exhibit a set of locomotor abnormalities. They display a general instability and whole body tremor, are slow at initiating movement, show reductions in purposeful action, and perform poorly at locomotor tests such as mid-air righting. L-dopa administration or fetal midbrain transplants reverse the majority of the symptoms, resembling the observations made on Parkinson's disease patients. These features make the AS/AGU strain a useful model for movement disorders due in significant part to failure of the dopaminergic transmission system. Crosses of AS/AGU to other laboratory rat strains point to a single recessive mutation with essentially complete penetrance (agu/agu) as the cause of the abnormal phenotype. There is no evidence of sex linkage or maternal inheritance. In the absence of any evidence of the function of the agu gene product, positional cloning of this locus was begun. The first step was the establishment of a genetic map location for the agu locus. A large series of microsatellite markers were analysed and used to identify which of the strains PVG, BN, and F344 differed to a greater extent from AS/AGU. Differences at 43%, 62% and 47% of the loci were recorded, respectively. BN and F344 were therefore selected as the reference strains in backcrosses to AS/AGU, in an attempt to maximise the number of informative markers which could be used to type the progeny.
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Bradley, Maria. "Genetic studies of atopic dermatitis /." Stockholm : [Karolinska institutets bibl.], 2001. http://diss.kib.ki.se/2001/91-7349-085-7/.
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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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Köhn, Linda. "Genetic mapping of retinal degenerations in Northern Sweden." Doctoral thesis, Umeå universitet, Medicinsk och klinisk genetik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-27004.
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Inherited retinal degenerations are a group of disorders characterised by great genetic heterogeneity. Clinically, they can be divided into two large groups of diseases, those associated with night blindness, e.g. retinitis pigmentosa (RP), and those with macular malfunction, e.g. cone/cone-rod dystrophy (COD/CORD). This thesis is focused on finding the genetic basis of disease in families with autosomal dominant COD, autosomal dominant RP, and Bothnia dystrophy (BD), a regional variant of RP. A variant of COD was previously mapped to 17p12-p13 in a family from northern Sweden. One additional family originating from the same geographical area was included in fine mapping of this chromosome region. Using 12 microsatellite markers in linkage and haplotype analysis, the region was refined from 26.9 to 14.3 cM. A missense mutation, Q626H, in an evolutionarily conserved region of PITPNM3, phosphatidylinositol transfer membrane-associated protein, was identified. The mutation segregated with the disease in both families and was absent from normal control chromosomes. PITPNM3 is a human homologue of the Drosophila retinal degeneration (rdgB) protein, which is highly expressed in the retina and has been proposed to be required for membrane turnover of photoreceptor cells. With the intention of establishing the global impact that PITPNM3 has on retinal degenerations 165 DNA samples from COD and CORD patients were obtained from Denmark, Germany, the UK, and USA and screened for mutations. The Q626H mutation found in the Swedish families was also found in one British family and a novel Q342P variant was detected in a German patient. In addition, two intronic variants were identified: c.900+60C>T and c.901-45G>A. Thus, we concluded that mutations in PITPNM3 represent a rare cause of COD worldwide. In two large families from northern Sweden showing autosomal dominant RP with reduced penetrance, the disease locus was mapped using genome-wide linkage analysis to 19q13.42 (RP11). Since mutation screening of eight genes on 19q13.42 revealed no mutations, multiplex ligation-dependent probe amplification (MLPA) was used to screen for large genomic abnormalities in PRPF31, RHO, RP1, RPE65, and IMPDH1. A large deletion spanning 11 exons of PRPF31 and three genes upstream was identified. Using long-range PCR, the breakpoints of the deletion were identified and the size of the deletion was determined to encompass almost 59 kb. BD is an autosomal recessive type of RP with high prevalence in northern Sweden. The disease is associated with a c.700C>T mutation in RLBP1. In a screening of recessive RP in northern Sweden, 67 patients were found to be homozygous for c.700C>T and 10 patients were heterozygous. An evaluation with arrayed primer extension (APEX) technology revealed a second mutation, c.677T>A, in RLBP1 giving rise to compound heterozygosity in these patients. In addition, a c.40C>T exchange in CAIV was detected in a patient with BD and in 143 healthy blood donors. The c.40C>T substitution in CAIV has been reported to cause autosomal dominant RP in South African families with European ancestry. However, in the population of northern Sweden it appears to be a benign polymorphism. In summary, a first mutation in PITPNM3, encoding a human homologue of the Drosophila retinal degeneration protein, was detected in two large families with COD. A large deletion in PRPF31 was discovered in two families with autosomal dominant RP showing reduced penetrance and in 10 patients BD was shown to be caused by two allelic mutations in RLBP1.
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Dudley, Roy. "Genetic mapping of Armillaria ostoyae using RAPD markers." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0004/MQ44087.pdf.
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Åkesson, Eva. "Genetic mapping and association analysis in multiple sclerosis /." Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-174-1/.
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Dudley, Roy 1972. "Genetic mapping of Armillaria ostoyae using RAPD markers." Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=20796.
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We report here the use of RAPD-PCR (Random Amplified Polymorphic DNA - Polymerase Chain Reaction) to identify segregating loci in the haploid progeny of an Armillaria ostoyae basidiocarp and the construction of the first genetic linkage map of this fungus, one of the causal species of Armillaria Root Disease. Upon screening 75 RAPD primers, 18 were found to identify a total of 43 loci segregating with a 1 : 1 Mendelian ratio. These loci were analysed for linkage among 58 monospore progeny. The map constructed with Mapmaker (LOD = 3.0, r = 0.38) was confirmed by GMendel (LOD = 1.5, r = 0.38). This map arranged 30 loci into 6 linkage groups and 4 linkage pairs. Thirteen markers remained unlinked. Using the Kosambi mapping function the linked loci accounted for approximately 450 cM and the genome was estimated to be 1600 cM. This preliminary map covers approximately 28% of the A. ostoyae genome.
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Zhuang, Nan. "Logic synthesis and technology mapping using genetic algorithms." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286760.
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Stone, Caroline. "Molecular and genetic mapping of the haemochromatosis locus." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306980.
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Cooper, Anneli Clare. "Linkage mapping and genetic analysis of Trypanosoma brucei." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/1656/.
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Trypanosoma brucei is a protozoan parasite of major public health and economic importance in sub-Saharan Africa, where it is the causative agent of sleeping sickness in man and Nagana in cattle. The complete genome sequence of T.brucei is now available and the diploid genetic system has recently been demonstrated to be Mendelian. This opens up the possibility of using a classical genetic approach to identify genetic loci that determine important phenotypic traits in this parasite, such as host specificity, drug resistance, and pathogenicity. A genetic map of the non human-infective subspecies, T.b.brucei, has already been assembled and successfully used in quantitative trait analysis of a number of traits specific to this pathogen. This thesis describes the construction of a separate genetic map for the sub-species responsible for > 90% of human African trypanosomiasis infections, T.b.gambiense, which differs significantly from T.b.brucei in many key phenotypes. The genetic linkage map was constructed from the analysis of 119 polymorphic microsatellite markers in a population of 38 F1 progeny, obtained from the genetic cross of a T.b.gambiense group 2 strain, STIB 386, with a T.b.brucei strain, STIB 247. Eleven major linkage groups were resolved, one for each of the megabase chromosomes, resulting in a total genetic map length of 733 cM, and an average map unit size of 24 Kb/cM. The map provides a 90% probability of a marker being within 268 Kb of any genetic locus. A comparative analysis of the T.b.gambiense and T.b.brucei genetic maps revealed synteny and marker order to be conserved between the two sub-species. However, variation was observed in the location of regions of high and low recombination frequency (hot and cold spots) in the two maps. The genetic linkage map presented here is the first available for T.b.gambiense and can now be utilised to find the location within the genome of genes responsible for phenotypic traits in this clinically important sub-species. These traits include human infectivity, tsetse transmissibility and virulence, in addition to sensitivity to the trypanocidal drug, pentamidine, for which phenotypic variation between the parents was characterised both in vitro and in vivo in this thesis. The ability of the T.brucei genetic maps to pinpoint loci underlying phenotypic variation is limited by the number of recombination events, and therefore progeny, available for analysis. To increase the utility of this approach for future studies, an improved method for progeny isolation from uncloned genetic cross populations was also developed. This in vitro bloodstream cloning procedure is scalable and efficient, and replaces a time consuming and technically demanding in vivo method. Twelve new progeny clones were isolated by this approach during the trial and incorporated into the analysis, representing a step toward a higher resolution second-generation genetic map. Finally, whilst undertaking genotyping analysis with microsatellite markers the development of spontaneous chromosome 10 abnormalities was observed. A detailed investigation identified seven laboratory-adapted T.brucei lines in which loss of heterozygosity appeared to have occurred. These alterations to the karyotype significantly exceeded the well-characterised genomic rearrangements of subtelomeric regions that are frequently associated with antigenic variation in African trypanosomes. Microsatellite analysis, pulsed field gel electrophoresis and Illumina next generation sequencing demonstrated these changes to be the product of mitotic recombination events in the chromosome core, resulting in an extensive loss of heterozygosity of up to 75% of the chromosome and correlated with an improved growth phenotype. Further work is now required to determine the extent and frequency with which these abnormalities might occur, however these findings do highlight the potential instability of the molecular karyotype of T.brucei in prolonged in vitro culture.
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Ahmed, Helal Uddin. "Mapping stress tolerance genetic loci in Arabidopsis thaliana." Thesis, University of Newcastle Upon Tyne, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246628.
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Wang, Xiao Yu. "Genetic and physical mapping of Arabidopsis and Brassica." Thesis, University of Birmingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433979.
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Baird, Nathan Alder. "Hypoxic gene regulation and high-throughput genetic mapping. /." Connect to title online (ProQuest), 2008. http://proquest.umi.com/pqdweb?did=1525703731&sid=1&Fmt=2&clientId=11238&RQT=309&VName=PQD.
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Thesis (Ph. D.)--University of Oregon, 2008.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 45-52). Also available online in ProQuest, free to University of Oregon users.
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Köhn, Linda. "Genetic mapping of retinal degenerations in Northern Sweden." Umeå : Umeå university, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-27004.
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Baird, Nathan Alder 1979. "Hypoxic gene regulation and high-throughput genetic mapping." Thesis, University of Oregon, 2008. http://hdl.handle.net/1794/7505.
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xi, 52 p. ; ill. (some col.) A print copy of this title is available through the UO Libraries under the call number: SCIENCE QH445.2 .B35 2008Activation of Heat shock proteins (Hsps) is critical to adaptation to low oxygen levels (hypoxia) and enduring the oxidative stress of reoxygenation. Hsps are known to be regulated by Heat shock factor (Hsf), but my results demonstrate an unexpected regulatory link between the oxygen sensing and heat shock pathways. Hsf transcription is upregulated during hypoxia due to direct binding by Hypoxia-inducible Factor-1 (HIF-1) to HIF-1 response elements in an Hsf intron. This increase in Hsf transcripts is necessary for full Hsp induction during hypoxia and reoxygenation. The HIF-1-dependent increase in Hsps has a functional impact, as reduced production of Hsps decreases viability of adult flies exposed to hypoxia and reoxygenation. Thus, HIF-1 control of Hsf transcriptional levels is a regulatory mechanism for sensitizing heat shock pathway activity in order to maximize production of protective Hsps. This cross-regulation represents a mechanism by which the low oxygen response pathway has assimilated complex new functions by regulating the heat shock pathway's key transcriptional activator. Beyond studying the regulation of specific genes. I have also developed a method to identify small, yet important, changes within entire genomes. Genetic variation is the foundation of phenotypic traits, as well as many disease states. Variation can be caused by inversions, insertions, deletions, duplications, or single nucleotide polymorphisms (SNPs) within a genome. However, identifying a genetic change that is the cause of a specific phenotype or disease has been a difficult and laborious task for researchers. I developed a technique to quickly and accurately map genetic changes due to natural phenotypic variation or produced by genetic screens. I utilized massively parallel, high-throughput sequencing and restriction site associated DNA (RAD) markers, which are short tags of DNA adjacent to the restriction sites. These RAD markers generate a genome-wide signature of fragments for any restriction enzyme. Taken together with the fact that the vast majority of organisms have SNPs that disrupt restriction site sequences, the differences in the restriction fragment profiles between individuals can be compared. In addition, by using bulk segregant analysis, RAD tags can be used as high-density genetic markers to identify a genetic region that corresponds to a trait of interest. This dissertation includes both previously published and unpublished co-authored materials.
Adviser: Eric Johnson
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Mulley, John Charles. "Genetic marker studies in humans /." Title page, contents and summary only, 1985. http://web4.library.adelaide.edu.au/theses/09PH/09phm958.pdf.
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Tang, Ling-fung Paul, and 鄧凌鋒. "Dissecting the genetics of complex trait in mouse: an attempt using public resources and in-houseknockout." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B43572170.
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Lambert, Carol-Ann. "A novel marker technique : using miniature inverted-repeat transposable elements (MITEs) in combination with resistant gene analogues (RGAs)." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52117.
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Thesis (PhD)--Stellenbosch University, 2001.ENGLISH ABSTRACT: Given the organisation of the maize genome as well as demands placed on the saturation of molecular linkage maps it would be desirable to identify informative molecular markers that is located or linked to genic rich areas. Sequences of gene products from different gene classes were investigated. Proteins containing a nucleotide binding site (NBS) and leucine-rich repeat (LRR) region comprise the largest class of disease resistance proteins. Resistant gene analogue (RGA) primers belonging to this specific class were derived from previous published literature studies. By means of similarity studies of short stretches of conserved amino acid and DNA sequences, primers were developed that belonged to the peroxidase and reductase gene classes. A novel class of transposable element was identified, that occurred in the gene rich areas of a diverse range of grass genomes. Of all the MITE families described so far, the Heartbreaker (Hbr) and Hb2 family elements were of particular interest. The unique properties of MITEs, especially their high copy number, polymorphism, stability and preference for genic areas together with the RGA primers, were exploited to develop a new marker technique for the isolation of a class of molecular marker with a strong preference for genic areas. Using the publicly available recombinant inbred population, Tx303 x C0159, 196 MITE/RGA markers were added to the existing recombinant inbred linkage map consisting of ±1033 already established markers. It became apparent that just like loci for disease resistance, the 196 MITE/RGA fragments were not randomly distributed across the maize genome but occurred in clusters spread across the ten maize chromosomes. Ninety-two (92) of the MITE/RGA fragments showed significant correlation to previously mapped maize resistance genes. To establish the conservation and specificity of both the Hbr and Hb2 elements, sequences of 19 MITE/RGA fragments were ascertained. When comparing the partial MITE element sequences from these fragments, a high degree of element conservation was observed. One fragment showed good sequence correlation to a NADPH He Toxin reductase protein product and mapped to the same chromosomal location as the hm1 gene locus in maize. This fragment can be considered a candidate gene for resistance against the pathogen, Helminthosporium carbonum. The Hbr primer used proved to be very specific for the Heartbreaker MITE element, this was in contrast to the non-specificity of the Hb2 primer. The applicability of this technique was tested on two maize diseases that cause immense damage in the maize production industries in South Africa. Fourteen MITE/RGA markers were used to fine map the putative chromosomal locations for the HtN1, Ht1, Ht2 and Ht3 genes that confer resistance. against Setosphaeria turcica, the northern corn leaf blight (NelS) pathogen in maize. Three MITE/RGA fragments were identified that aided in the saturation of the linkage map for quantitative trait resistance (QTl) against gray leaf spot (GlS) in maize. This novel MITE/RGA technique presented a unique opportunity to search for additional candidate genes by using polymerase chain reaction (peR) analysis. When compared to the conventional amplified fragment length polymorphism (AFLP) technique, the MITE/RGA technique proved to be just as efficient but was more cost effective and less time consuming.
AFRIKAANSE OPSOMMING: Die organisasie van die mielie genoom as ook die vereistes wat daar geplaas word op die versadiging van koppelingskaarte, vereis dat daar meer klem geplaas word op die ontwikkeling van molekulêre tegnieke wat merkers in geenryke areas identifiseer. Die volgordes van geenprodukte, wat behoort tot verskillende geenklasse, is deeglik bestudeer. Proteïenprodukte wat bestaan uit 'n nukleotiedbindingsarea (NBA) en 'n leusienryke herhalende (LRH) area is een van die grootste klasse waaronder siekteweerstandsproteïene sorteer. Polimerase kettingreaksie (PKR) inleiers wat behoort tot hierdie spesifieke klas, is verkry vanuit vorige publikasies. Deur kort gekonserveerde aminosuur en DNS volgordes te vergelyk is inleiers ontwikkel wat behoort tot die peroksidase en reduktase gene klasse. 'n Nuwe klas transponeerbare elemente wat voorkom in die geenryke areas van diverse gras genome, is geïdentifiseer. Van al die miniatuur inversie herhalende transponeerbare elemente (MITE) wat al geïdentifiseer is, is die twee elemente, Heartbreaker (Hbr) en Hb2, van groot belang. Unieke eienskappe van die MITEs, veral hul hoë kopie aantal, polimorfiese-indeks, stabiliteit asook voorkeur vir geenryke areas, tesame met die weerstandsgeen analoë (WGA) inleiers, is gebruik om 'n nuwe merker tegniek te ontwikkel. Hierdie nuwe tegniek identifiseer 'n klas merker wat 'n sterk voorkeur het vir geenryke areas. Deur gebruik te maak van die openbare beskikbare rekombinante ingeteelde (RI) populasie, Tx303 x C0159, is 196 MITE/WGA-merkers gekarteer op die bestaande RIL koppelingskaart, wat alreeds bestaan uit ±1033 gevestigde merkers. Net soos die lokusse vir siekteweerstand het dit geblyk dat hierdie 196 merkers in groepe voorkom wat verspreid is oor die tien mielie chromosome. Twee-en-negentig (92) van die 196 gekarteerde MITE/WGA-merkers het betekenisvolle korrelasie gewys met reeds gekarteerde mielie weerstandsgene. Die volgordes van 19 MITE/WGAfragmente is bepaal om sodoende die spesifisiteit en mate van konservering van die Hbr and Hb2 elemente te bereken. 'n Hoë mate van element konservering is waargeneem. Een fragment het In baie goeie volgorde korrelasie gewys met In NADPH HG toksien reduktase proteïen produk en karteer op dieselfde chromosomale posisie as die hm1 geen lokus. Hierdie fragment kan gesien word as In kandidaatgeen vir weerstand teen die mielie patogeen, Helminthosporium carbonum. Die toepasbaarheid van hierdie tegniek is getoets op twee siekte toestande, wat lei tot groot verliese in die mielie industrie, in Suid-Afrika. Veertien van die MITE/WGAmerkers is gebruik om die waarskynlike chromosomale posisies van die HtN1, Ht1, Ht2 en Ht3 gene, wat weerstand bied teen Setosphaeria turcica, die noordelike mielie blaarvlek (NMBV) patogeen, fyner te karteer. Drie MITE/WGA fragmente is geïdentifiseer wat gehelp het in die versadiging van die koppelingskaart vir die kwantitatiewe kenmerk weerstandbiedenheid (KKW) teen grys blaarvlek (GBV) in mielies. Deur gebruik te maak van polimerase kettingreaksie (PKR) analise, verskaf hierdie tegniek die moontlikheid om te soek vir addisionele kandidaatgene. Hierdie tegniek is ook vergelyk met die konvensionele geamplifiseerde fragment lengte polimorfisme (AFLP) tegniek. Daar is gevind dat die nuwe tegniek net so informatief is, maar wel meer koste effektief en tyd besparend.
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Lehmensiek, Anke. "Genetic mapping of gray leaf spot resistance genes in maize." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51776.
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Thesis (PhD)--Stellenbosch University, 2000.ENGLISH ABSTRACT: Gray leaf spot (GLS) of maize, caused by the fungus Cercospora zeae-maydis, can reduce grain yields by up to 60% and it is now recognized as one of the most significant yield-limiting diseases of maize in many parts of the world. The most sustainable and long-term management strategy for GLS will rely heavily on the development of high-yielding, locally adapted GLS resistant hybrids. Molecular markers could be useful to plant breeders to indirectly select for genes affecting GLS resistance and to identify resistance genes without inoculation and at an early stage of plant development. Only two studies in the USA have examined quantitative trait loci (QTL) association with GLS resistance. The aim of this study was to map GLS resistance genes in a resistant Seed Co LTD, Zimbabwean inbred line. Molecular markers linked to the GLS resistance QTL were identified by using the amplified fragment length polymorphism (AFLP) technique together with bulked segregant analysis. Eleven polymorphic AFLP fragments were identified and converted to sequence-specific PCR (polymerase chain reaction) markers. Eight of the 11 converted AFLP markers were added to the maize marker database of the University of Stellenbosch. Five of the 8 converted AFLP markers were polymorphic between the resistant and the susceptible parent. They were amplified on the DNA of 230 plants of a segregating F2 population and linkage analysis was performed with MAPMAKER/EXP. Two linkage groups consisting of two markers each, with a linkage distance of 10.4 cM (LOD 22.83) and 8.2 cM (LOD 55.41) between the two markers, were identified. QTL mapping with MAPMAKER/QTL confirmed the presence of QTL in both linkage groups. Two publicly available recombinant inbred families (Burr et a/., 1988) were used to localize the converted AFLP markers on the genetic map of maize. The QTL, which were identified with the AFLP markers, were mapped to chromosomes 1 and 5. Another AFLP marker was mapped to chromosome 2 and a further to chromosome 3. To obtain more precise localizations of the QTL on chromosomes 1 and 5, sequence-tagged site markers and microsatellite markers were used. The markers were amplified on the DNA of the 230 plants of the F2 population and linkage analysis was performed with MAPMAKER/EXP. The order of the markers was in agreement with the UMC map of the Maize Genome Database. Interval mapping using MAPMAKERlQTL and composite interval mapping using QTL Cartographer were performed. The QTL on chromosome 1 had a LOD score of 21 and was localized in bin 1.05/06. A variance of 37% was explained by the QTL. Two peaks were visible for the QTL on chromosome 5, one was localized in bin 5.03/04 and the other in bin 5.05/06. Both peaks had a LOD score of 5 and 11% of the variance was explained by the QTL. To test the consistency of the detected QTL, the markers flanking each QTL were amplified on selected plants of two F2 populations planted in consecutive years and regression analysis was performed. Both the QTL on chromosome 1 and the QTL on chromosome 5 were detected in these populations. Furthermore, the presence of a QTL on chromosome 3 was confirmed with these populations. A variance of 8 -10% was explained by the QTL on chromosome 3. In this study, a major GLS resistance QTL was thus mapped on chromosomes 1 and two minor GLS resistance QTL were mapped on chromosomes 3 and 5 using a resistant Seed Co LTD, Zimbabwean inbred line. Markers were identified which could be used in a marker-assisted selection program to select for the GLS resistance QTL.
AFRIKAANSE OPSOMMING: Grys blaarvlek (GBV) van mielies, veroorsaak deur die swam Cercospora zeaemaydis, kan graanopbrengs met tot 60% verlaag en word beskou as een van die vernaamste opbrengs-beperkende siektes wêreldwyd. Die toepaslikste langtermyn stragtegie vir GBV beheer sal wees om plaaslike mieliebasters met hoë opbrengs en GBV weerstand te ontwikkel. Molekulêre merkers kan nuttig deur plantetelers gebruik word om weerstandsgene te selekteer. Seleksie is moontlik in die afwesigheid van inokolum en op 'n vroeë stadium van plant ontwikkeling. Slegs twee vorige studies (in die VSA) het kwantitatiewe-kenmerk-Iokusse (KKL), vir GBVweerstand ondersoek. Die doel van hierdie studie was om die GBV weerstandsgene in 'n weerstandbiedende ingeteelde lyn (Seed Co BPK, Zimbabwe) te karteer. Molekulêre merkers gekoppel aan die GBV weerstands KKL is geïdentifiseer deur gebruik te maak van die geamplifiseerde-fragmentlengte-polimorfisme- (AFLP-) tegniek en gebulkte-segregaat-analise. Elf polimorfiese merkers is geïdentifiseer en omgeskakel na volgorde-spesifieke PKR (polimerase kettingreaksie) merkers. Agt van die elf omgeskakelde AFLP-merkers is by die mieliemerker databasis van die Universiteit van Stellenbosch gevoeg. Vyf van die 8 omgeskakelde AFLP-merkers was polimorfies tussen die bestande en vatbare ouers. Hulle is geamplifiseer op die DNA van 230 plante van 'n segregerende F2-populasie en is gebruik in 'n koppelingstudie met MAPMAKER/EXP. Twee koppelingsgroepe, elk bestaande uit twee merkers, met onderskeidelik koppelingsafstande van 10.4 eM (LOD 22.83) en 8.2 eM (LOD 55.41) tussen die merkers, is geïdentifiseer. KKL-kartering het getoon dat KKL in albei koppelingsgroepe aanwesig is. Twee kommersieël beskikbare, rekombinant-ingeteelde families (Burr et aI., 1988) is gebruik om die omgeskakelde AFLP-merkers op die mielie genetiese kaart te plaas. Die KKL wat met die AFLP-merkers geïdentifiseer is, is gekarteer op chromosome 1 en 5. 'n Verdere AFLP-merker is op chromosoom 2 gekarteer en 'n ander op chromosoom 3. Ten einde die KKL op chromosome 1 en 5 meer akkuraat te karteer, is volgordege- etikeerde en mikrosatelliet merkers gebruik. Die merkers is geamplifiseer op die DNA van die 230 plante van die F2-populasie en koppelings-analises is uitgevoer. Die volgorde van die merkers was dieselfde as die van die UMC-kaart in die Mielie Genoom Databasis. Interval kartering met MAPMAKER/QTL en komposiet interval kartering met QTL Cartographer is uitgevoer. Die KKL op chromosoom 1 het 'n LOD-telling van 21 gehad en is in bin 1.05/06 geplaas. Die KKL was verantwoordelik vir 37% van die variansie. Twee pieke was onderskeibaar vir die KKL op chromosoom 5, een in bin 5.03/04 geleë en die ander in bin 5.05/06. Elke piek het 'n LOD-telling van 5 gehad en die twee KKL was verantwoordelik vir 11% van die variansie. Om die herhaalbaarheid van die effek van die KKL te toets is die merkers naaste aan elke KKL geamplifiseer op geselekteerde plante van twee F2-populasies wat in opeenvolgende jare geplant is. Regressie analise is op die data gedoen. Beide die KKL op chromosoom 1 en die KKL op chromosoom 5 kon in hierdie populasies geïdentifiseer word. Verder kon die aanwesigheid van 'n verdere KKL op chromosoom 3 in hierdie populasies bevestig word. Laasgenoemde KKL was verantwoordelik vir 8-10% van die totale variansie. In hierdie studie is daar dus 'n hoof GBV-weerstands KKL gekarteer op chromosoom 1 en twee kleiner GBV-weerstands KKL gekarteer op chromosome 3 en 5. Merkers is geïdentifiseer wat moontlik in merker-gebaseerdetelingsprogramme gebruik kan word om plante te selekteer wat die GBVweerstands KKL het.
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Romano, Eduardo O. "Selection indices for combining marker genetic data and animal model information /." This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09192009-040546/.
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Ramburan, Viresh Premraj. "Genetic mapping of adult plant stripe rust resistance in the wheat cultivar Kariega." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53438.
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Thesis (PhD (Agric)) -- Stellenbosch University, 2003.ENGLISH ABSTRACT: Stripe (yellow) rust of wheat, caused by Puccinia striiformis f.sp. tritici, was first detected as a single introduction into South Africa in 1996. Two additional pathotypes have since been identified. Control of the disease may be achieved by use of genetic adult plant resistance (APR) as is present in the local cultivar 'Kariega'. The aim of this project was to understand the genetic basis of the APR in 'Kariega' to facilitate breeding of new varieties with genetic resistance to stripe rust. A partial linkage map of a 'Kariega X Avocet S' doubled haploid population covering all 21 wheat chromosomes was generated using 208 DNA markers, viz, 62 SSR, 133 AFLP, 3 RGA and 10 SRAP markers, and 4 alternative loci. The different marker techniques detected varying polymorphism, viz, overall SSR: 46%, AFLP: 7%, SRAP: 6% and RGA: 9%, and the markers produced low levels of missing data (4%) and segregation distortion (5%). A significant feature of the linkage map was the low polymorphism found in the D genome, viz, 19% of all mapped DNA markers, 11% of all AFLP markers and 30% of the total genome map distance. A region exhibiting significant segregation distortion was mapped to chromosome 4A and a seedling resistance gene for stem rust (Puccinia graminis f.sp . tritici), Sr26, mapped to chromosome 6A close to three SSR markers. The leaf tip necrosis gene, Ltn, which was also segregating in the population, mapped to chromosome 7D. Protocols for SRAP and RGA were optimised, and SRAP marker use in wheat genetic linkage studies is reported for the first time. The linkage map was used together with growth chamber and replicated field disease scores for QTL mapping. Chromosomes showing statistically significant QTL effects were then targeted with supplementary SSR markers for higher resolution mapping. The quality of disease resistance phenotypic data was confirmed by correlation analysis between the different scorers for reaction type (0.799±0.023) and for transformed percentage leaf area infected (0.942±0.007). Major QTL were consistently identified on chromosome 7D (explaining some 25-48% of the variation) and on chromosome 2B (21-46%) using transformed percentage leaf area infected and transformed reaction type scores (early and final) with interval mapping and modified interval mapping techniques. Both chromosomal regions have previously been identified in other studies and the 7D QTL is thought likely to be the previously mapped APR gene Yr 18. Minor QTL were identified on chromosomes lA and 4A with the QTL on 4A being more prominent at the early field scoring for both score types. A QTL evidently originating from 'Avocet S' was detected under growth chamber conditions but was not detected in the field, suggesting genotype-environment interaction and highlighting the need for modifications of growth chamber conditions to better simulate conditions in the field. The genetic basis of the APR to stripe rust exhibited by 'Kariega' was established by mapping of QTL controlling this trait. The linkage map constructed will be a valuable resource for future genetic studies and provides a facility for mapping other polymorphic traits in the parents of this population with a considerable saving in costs.
AFRIKAANSE OPSOMMING: Streep of geelroes van koring word veroorsaak deur Puccinia striiformis f. sp tritici, en is die eerste keer in 1996 in Suid-Afrika na introduksie van 'n enkele patotipe waargeneem. Twee verdere patotipes is sedertdien in Suid-Afrika gei"dentifiseer. Beheer van die siekte word veral moontlik gemaak deur die gebruik van genetiese volwasseplantweerstand soos gei"dentifiseer in die plaaslike kultivar 'Kariega'. Die doel van hierdie studie was om die genetiese grondslag van die streeproesweerstand te ontrafel ten einde die teling van nuwe bestande kultivars moontlik te maak. 'n Verdubbelde haplo1ede populasie uit die kruising 'Kariega X Avocet S' is aangewend om 'n gedeeltelike koppelingskaart vir die volle stel van 21 koring chromosome saam te stel. Die kaart het uit 208 DNA merkers, nl., 62 SSR, 133 AFLP, 3 RGA, 10 SRAP merkers en 4 ander lokusse bestaan. Totale polimorfisme wat deur die verskillende merkersisteme opgespoor is, was as volg: SSR: 46%, RGA: 9%, AFLP: 7% en SRAP: 6%. Die mate van ontbrekende data was gering (4%) asook die mate van segregasie distorsie (5%) van 'n enkele geval wat op chromosoom 4A gekarteer is. 'n Prominente kenmerk van die koppelingskaart is die relatiewe gebrek aan polimorfiese merkers op die D-genoom, nl., slegs 19% van alle DNA merkers en 11% van alle AFLP merkers wat slegs 30% van die totale genoom kaartafstand bestaan het. Die stamroes (Puccinia graminis f. sp. tritici) saailingweerstandsgeen, Sr26, karteer op chromosoom 6A naby drie SSR merkers. Die geen vir blaartipnekrose, Ltn, karteer op chromosoom 7D. Protokolle vir SRAP en RGA merkers is ge-optimiseer en gebruik van SRAP merkers in koppelings-analise word vir die eerste keer in koring gerapporteer. Die koppelingskaart is in kombinasie met groeikamerdata en gerepliseerde veldproefdata gebruik om die gene (QTL) vir volwasseplant streeproesweerstand te karteer. Chromosome met statisties betekenisvolle QTL is met aanvullende SSR merkers geteiken om die resolusie van kartering verder te verhoog. Die kwaliteit van fenotipiese data, soos in die proewe aangeteken, is bevestig deur korrelasies te bereken tussen lesings geneem deur onafhanklike plantpataloe (0.799 ± 0.023 vir reaksietipe en 0.942 ± 0.007 vir getransformeerde persentasie blaaroppervlakte besmet). Hoofeffek QTL vir die twee maatstawwe van weerstand is deur middel van die metodes van interval QTL kartering en gemodifiseerde interval QTL kartering konsekwent op chromosome 7D (25-48% van variasie verklaar) en 2B (21-46% van variasie verklaar) ge"identifiseer. In vorige studies is aangetoon dat beide chromosome 7D en 2B QTL vir volwasseplant streeproesweerstand dra. Die 7D QTL is waarskynlik die weerstandsgeen, Yr 18. QTL met klein effekte op weerstand is op chromosome lA en 4A ge"identifiseer. Die effek van laasgenoemde geen was meer prominent in die velddata in die vroee datum van weerstandsbeoordeling. Een QTL, afkomstig van 'Avocet S', is slegs onder groeikamertoestande identifiseerbaar. Dit dui op moontlike genotipe-omgewing wisselwerking en beklemtoon die noodsaaklikheid om aanpassings te maak in groeikamertoestande vir beter simulasie van veldproeftoestande. Die genetiese grondslag van volwasseplantweerstand teen streeproes in die kultivar 'Kariega' is deur QTL kartering bepaal. Die 'Kariega X Avocet S' koppelingskaart kan as 'n waardevolle basis dien vir toekomstige genetiese ontledings van ander polimorfiese kenmerke in die populasie.
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Magnusson, Veronica. "Genetic studies on Systemic Lupus Erythematosus : A fine mapping and candidate gene approach." Doctoral thesis, Uppsala University, Department of Genetics and Pathology, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-2869.
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Linkage in the 2q37 region was evaluated using microsatellite markers in multi-case families from Sweden, Iceland and Norway. Both the two-point and the multipoint linkage analysis show highly significant LOD scores (Z=4.51 and 6.03, respectively). Linkage disequilibrium mapping indicates that some association exists in this region. The PDCD1 gene was suggested as a candidate gene within the 2q37 locus due to its importance in immune regulation. Indeed, one haplotype, described by the presence of allele A of the PD1.3 SNP located within intron 4 of this gene, shows linkage to SLE in the Nordic families. The PD1.3A allele is also found to be strongly associated in familiar and sporadic cases of SLE in Europeans and Mexicans. Functional studies further support PD1.3A to be a susceptibility allele for SLE.
The 1q23 region, containing the genes for the low affinity Fcγ receptors, was fine mapped using single- and multi- case families of various origins. Genetic variants of those genes were analysed and association is found to both the risk alleles of FcγRIIA and FcγRIIIA in all families. In these families, a single haplotype carrying both risk alleles is predominantly transmitted to patients with SLE, suggesting a presence of linkage disequilibrium between those two genes. FcγRIIA and FcγRIIIA are also found to be associated to SLE and lupus nephritis in a case-control cohort from Sweden. In the same cohort, the PD1.3A allele shows strong association to lupus nephritis. We suggest that there may be an additive effect between FcγRIIA and PDCD1, since having the disease-associated genotypes at both loci gives an increased risk for developing lupus nephritis.
Systemic Lupus Erythematosus (SLE) is a systemic autoimmune disorder with a complex multifactorial aetiology. Genetic studies suggest that several genes are involved in disease pathogenesis and that extended genetic heterogeneity is present.
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Dutton, Elizabeth R. "Mapping studies on mouse distal Chromosome 2." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299401.
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Liu, Zhiyong Michael. "Mapping physical topology with logical topology using genetic algorithm." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ62245.pdf.
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Craig, Nicola Jane. "Genetic and physical mapping of the rat agu locus." Thesis, University of Glasgow, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341722.
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Malas, Stavros. "Genetic and physical mapping studies on mouse chromosome 2." Thesis, University College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283659.
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Derry, Jonathan Michael James. "Genetic and physical mapping of the mouse X chromosome." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239109.
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Fytrou, Anastasia. "Drosophila immunity : QTL mapping, genetic variation and molecular evolution." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4742.
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Drosophila is involved in a wide range of interactions with parasites and pathogens (parasitoid wasps, bacteria, fungi, viruses). Drosophila hosts vary greatly at the species, population and individual level, in their response against such organisms, and much of this variation has a genetic basis. In this thesis I explored three aspects of this variation. First, using recombination mapping based on SNPs and a variation of bulk segregant analysis, I identified a QTL region on the right arm of the third chromosome of D. melanogaster associated with resistance to at least some of the parasitoid species / strains used in the experiments. The location of the QTL was further explored with deficiency complementation mapping and was narrowed down to the 96D1-97B1 region. The success of the deficiency mapping suggests that the resistant allele is not completely dominant. Second, I investigated patterns of molecular evolution in a set of immunity-related genes, using sequences from a D. melanogaster and a D. simulans population and a set of genes without known involvement in immunity for comparison. I found evidence that several of these genes have evolved under different selection pressure in each species, possibly indicating interactions with different parasites. The immunity genes tested appear to be evolving faster compared to non-immunity genes, supporting the idea that the immune system is evolving under strong selective pressure from parasites. Finally, in a D. melanogaster – sigma virus system, I measured genetic variation in the transmission of different virus genotypes, in different environments. There was poor correlation between temperatures, suggesting that environmental heterogeneity could constraint evolution of resistance (to virus transmission). The correlation between viral genotypes was also low, although relatively stronger for more closely phylogenetically related viral strains. Such interactions between host genotypes, virus genotypes and environmental conditions can maintain genetic variation in virus transmission.
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Hanley, Steven J. "Genetic mapping of important agronomic traits in biomass willow." Thesis, University of Bristol, 2003. http://hdl.handle.net/1983/ed4da27e-641a-4d0e-bbbf-8d21493a6a29.
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Wu, Song. "A robust approach for genetic mapping of complex traits." [Gainesville, Fla.] : University of Florida, 2008. http://purl.fcla.edu/fcla/etd/UFE0022399.
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Su, Dongzhe. "Application mapping on multiprocessor hardware platforms using genetic algorithms /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CSED%202009%20SU.
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Saffdar, Huma. "Rust resistance in wheat: genetic analysis and molecular mapping." Thesis, The University of Sydney, 2019. https://hdl.handle.net/2123/21377.
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Breeding for rust resistance in wheat relies on detailed understanding and availability of existing genetic diversity for rust resistance among global germplasm and knowledge of pathotypic variation among rust pathogens. This study involved assessment of genetic diversity for stem rust resistance in an international wheat nursery ZWB14, inheritance of stripe rust resistance in a common wheat landrace Aus27881 and molecular mapping of stripe rust resistance in genotype ZIZ13:69 imported from International Centre for Agricultural Research in the Dry Areas (ICARDA). All stage resistance (ASR) genes Sr8a, Sr17, Sr24, Sr30, Sr31 and Sr38 and adult plant resistance (APR) genes Sr2, Sr57 and Sr58 were present either singly or in different combinations in entries of ZWB14. Some entries were observed to carry additional uncharacterised resistance. Tri-genic inheritance of stripe rust resistance in Aus27881 was observed. Genotyping with Yr34 and Yr29 linked markers demonstrated the presence of these genes in Aus27881. Third locus that conditioned APR in Aus27881 appears to be new and needs further characterisation. Genotype ZIZ13:69 was demonstrated to carry ASR gene Yr1 and APR gene Yr29 based on greenhouse tests and marker genotyping, respectively. The targeted genotyping by sequencing (tGBS) assay of a set of RILs lacking Yr29 detected a new quantitative trait locus (QTL) on the long arm of chromosome 7D.
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Skipper, Lisa Marie. "Parkinson's disease susceptibility : genetic mapping in an isolated population." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1446678/.
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Parkinson's disease (PD) is an aetiologically complex, progressive and debilitating neurodegenerative disorder that primarily affects the elderly population. It is characterised clinically by the presence of motor symptoms including resting tremor, bradykinesia and rigidity; pathologically by neuronal loss within mid brain regions and intraneuronal inclusions comprising numerous protein aggregates. Disease risk factors are both environmental and genetic. To date, at least 10 genetic loci are implicated and specific mutations have been identified in SNCA, PRKN, UCH-Ll, DJ-1 and PINKL Variability within the MAPT gene has also been associated with disease risk. Population isolates are a powerful tool for the dissection of genetically complex disorders, due to expected genetic homogeneity and linkage disequilibrium (LD) levels. This project has focused upon a population isolate from Trondheim, central Norway, in which most individuals with PD show no family history of disease. In the first study of the genetic factors involved in PD within the Norwegian population, we chose to investigate recessive (PARK2, PARK6 and PARK7) and susceptibility (MAPT and PARK 10) loci, which may manifest as sporadic disease. Analysis of PRKN (PARK2) suggested that this locus contributes to PD in the Norwegian population and that the high frequency of the A82E mutation in the Trondheim community is due to a founder effect. In addition, a novel proline insertion mutation was identified. Detailed examination of the MAPT H1 haplotype associated with parkinsonism, showed that 'H1' consists of a group of related but distinct haplotypes, one of which is preferentially associated with PD. The variability most associated with disease was shown to lie at the 5' end of MAPT, encompassing exons 1 to 4. Candidate gene analysis and novel multipoint LD mapping methods at PARK10 identified two genes, EPS15 and NRDl, which may also contribute to PD risk. Further molecular genetic analysis will contribute to the understanding of pathogenic mechanisms through the use of cellular and animal models, and ultimately the development of both palliative and preventative therapies.
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Laimer, Christina. "Genetic Mapping of Increased Glutamic Acid in NOD Mice." Thesis, Umeå universitet, Biomedicinsk laboratorievetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-85070.
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Hsu, Ssucheng Jeff 1964. "Physical and genetic mapping on mouse proximal chromosome 18." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282617.
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An 8-Mb yeast artificial chromosome (YAC) contig has been constructed spanning 9 cM on mouse proximal chromosome 18. The contig consists of 49 YAC clones that cover roughly 15% of the chromosome. The map was assembled based on the presence or absence of 38 DNA microsatellites, from proximal DI8Mit109 through distal D18Mit68. The physical order of those microsatellite STSs have been assigned. The locations of 21 known genes including markers near twirler (Tw) and the recently isolated Niemann-Pick type C1 (Npc1), formerly designated as spm (sphingomyelinosis), are delimited on this physical map. Mouse Niemann-Pick disease type C1 (Npc1) is an autosomal recessive lipid storage disorder. We generated a high resolution linkage map in the 2.24 cM Npc1 critical region by typing 8 polymorphic markers in 2322 meioses. A minimal set of overlapping yeast artificial chromosome (YACs) has been assembled. The YAC 313-B-8 which covers this whole region, has been used to construct a cosmid library. Three cosmid contigs were built and one of them contained the Npc1 locus. Two (CA)n microsatellites were identified and characterized from the YAC derived cosmids. The most proximal cosmid contig overlaps with the markers near twirler gene (Tw). These identified YACs and cosmid clones will be an important resource for mouse geneticists wishing to further characterize the Npc1 gene and identify Tw and other genes in this region. The physical map and genetic linkage map were integrated to study the recombination frequencies in this particular mouse genome region. On average, it showed a recombination ratio of cM/Mb > 1.1. However, there is no recombination in the 300 Kb Npc1 critical region. We believe that the 703 bp deletion and 824 bp insertion of nonhomologous sequences in the mutation of Npc1 inhibits the occurrence of recombination in the region. These results confirm previous studies showing that recombination in mice is sensitive to heterozygous deletions or insertions of DNA fragments.
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Lorenzini, Eugenia <1993>. "Mapping new non-genetic dependencies in malignant pleural mesothelioma." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10287/1/PhD%20Thesis%20Eugenia%20Lorenzini.pdf.
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Malignant Pleural Mesothelioma (MPM) is a very aggressive cancer whose incidence is growing worldwide. MPM escapes the classical models of carcinogenesis and lacks a distinctive genetic fingerprint, keeping obscure the molecular events that lead to tumorigenesis. This severely impacts on the limited therapeutic options and on the lack of specific biomarkers, concurring to make MPM one of the deadliest cancers.
Here we combined a functional genome-wide loss of function CRISPR/Cas9 screening with patients’ transcriptomic and clinical data, to identify genes essential for MPM progression. Besides, we explored the role of non-coding RNAs to MPM progression by analysing gene expression profiles and clinical data from the MESO-TCGA dataset.
We identified TRIM28 and the lncRNA LINC00941 as new vulnerabilities of MPM, associated with disease aggressiveness and bad outcome of patients. TRIM28 is a multi-domain protein involved in many processes, including transcription regulation. We showed that TRIM28 silencing impairs MPM cells’ growth and clonogenicity by blocking cells in mitosis. RNA-seq profiling showed that TRIM28 loss abolished the expression of major mitotic players. Our data suggest that TRIM28 is part of the B-MYB/FOXM1-MuvB complex that specifically drives the activation of mitotic genes, keeping the time of mitosis.
In parallel, we found LINC00941 as strongly associated with reduced survival probability in MPM patients. LINC00941 KD profoundly reduced MPM cells’ growth, migration and invasion. This is accompanied by changes in morphology, cytoskeleton organization and cell-cell adhesion properties. RNA-seq profiling showed that LINC00941 KD impacts crucial functions of MPM, including HIF1α signalling.
Collectively these data provided new insights into MPM biology and demonstrated that the integration of functional screening with patients’ clinical data is a powerful tool to highlight new non-genetic cancer dependencies that associate to a bad outcome in vivo, paving the way to new MPM-oriented targeted strategies and prognostic tools to improve patients risk-based stratification.
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Stephens, Sarah H. "Fine mapping of the chromosome 15q13-14 schizophrenia linkage region /." Connect to full text via ProQuest. Limited to UCD Anschutz Medical Campus, 2008.
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Thesis (Ph.D. in Human Medical Genetics) -- University of Colorado Denver, 2008.Typescript. Includes bibliographical references (leaves 112-128). Free to UCD Anschutz Medical Campus. Online version available via ProQuest Digital Dissertations;
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Thompson, Eoin. "Exclusion mapping of polycystic kidney disease: A third locus." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1998. https://ro.ecu.edu.au/theses/1436.
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The aim of this research was to perform exclusion on a rare form of hereditary autosomal dominant polycystic kidney disease (ADPKD). To-date, two genes for ADPKD have been identified: PKDI which has been localized to the short arm of chromosome 16 and PKD2 which has been localized to the long arm of chromosome 4. However, a small number of families have been reported that have not shown linkage to either of these two loci, thus suggesting the existence of at least one additional locus (PKD3). Two families that are affected with ADPKD and do not show linkage to PKDI or PKD2 have participated in this study. Both families are of Bulgarian origin and between them contain 9 affected individuals. Even though these families are small, they are large enough to exclude a large proportion of the genome as the location of the PKD3 gene. The availability of these families and the discovery of other non PKD1/PKD2 families has provided a rare opportunity to perform exclusion mapping of the PKD3 gene which will eventually lead to mapping and cloning of this gene. A systematic search of the human genome was performed using polymorphic markers (from the Research Genetics screening set version 4a) which span the human genome at an average distance of 16cM. The results were then analysed statistically using the computer programs EXCLUDE, LINKAGE and GENEHUNTER. From this study the highest Lod score obtained was a multipoint Lod score of 2.95 on 22q 11.21 at marker D22S446. Two other regions also produced relatively high Lod scores, the first being on 4q22.1 at marker D4S1647 which produced a Lod score of 1.42 and the second region being on 11p15.2 at marker D11S902 which produced a Lod score of 1.41. These results provide a strong indication as to the location of the PKD3 gene however, before linkage can be claimed with any degree of certainty the sample size must be increased with the addition of other non PKD1/PKD2 families. This increases the possibility of obtaining a Lod score of 3.00 or greater and thus proving linkage to the PKD3 gene.
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Banerjee, Samprit. "Bayesian genome-wide QTL mapping for multiple traits." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2008. https://www.mhsl.uab.edu/dt/2009r/banerjee.pdf.
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Du, Plessis Jana. "Medium-throughput SNP genotyping and linkage mapping in Haliotis midae." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71701.
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Thesis (MSc)--Stellenbosch University, 2012.ENGLISH ABSTRACT: Haliotis midae (locally also known as perlemoen) is the largest of five endemic species found along the coast of South Africa. It is the only species with commercial value contributing to the exploitation of these animals. Due to declines of natural stocks, farming practices were established during the early 1990s in order to supply the international demand. To facilitate efficient breeding methods and ensure the sustainability of these commercial populations, genetic management, which can be accomplished with the use of molecular markers such as single nucleotide polymorphisms (SNPs), is necessary. Single nucleotide polymorphisms have become the markers of choice in various applications in aquaculture genetics due to their abundance in genomes, reduction in developmental costs and increased throughput of genotyping assays. Identification of SNPs in non-model species such as H. midae can be achieved by in silico approaches. In silico methods are suitable for de novo SNP identification and are both cost- and time-efficient. It is based on the analysis of multiple alignments where mismatches may be reported as candidate SNPs. Various medium-throughput genotyping methods are available to confirm putative SNPs, but the ideal method depends on factors such as cost, accuracy and multiplexing capacity. Although SNP markers can have various applications within the aquaculture environment the focus for this current study was saturating the linkage map of H. midae with additional markers. This would assist in the identification of quantitative trait loci associated with economically important traits, which in turn could ultimately be employed for marker-assisted selection and improved molecular breeding programs. In order to identify in silico SNPs, sequenced transcriptome data from a previous study was used and subjected to a series of criteria: minor allele frequency 10%, minimum coverage 80, 60 bp flanking regions. Selected loci were genotyped using a 192-plex assay with the Illumina GoldenGate genotyping assay with the VeraCode technology on the BeadXpress platform, in individuals from six mapping families. A conversion rate of 69.35% and global success rate of 76.34% was achieved. Polymorphic loci were subjected to linkage analysis using JoinMap® v.4.1 to create sex-average and sex-specific maps and to saturate the current linkage map for H. midae. Along with previously developed markers, 54% of the newly developed SNPs could be successfully incorporated into the linkage map of H. midae. A total of 18 linkage groups were observed with an average marker spacing of 6.9 cM and genome coverage of 79.1%. Bioinformatic analyses and setting stringent criteria to identify SNPs from sequenced transcriptomic data proved to be an efficient way for SNP discovery in the current study. Genotyping of the identified loci with the GoldenGate genotyping assay demonstrated a high success rate; providing a genotyping assay adequate for species with little genomic information. The linkage map created in this study illustrated the utility of SNP markers in conjunction with microsatellite markers for linkage map construction and the adequate marker spacing obtained provides a step closer to quantitative trait loci mapping in this species.
AFRIKAANSE OPSOMMING: Haliotis midae (plaaslik ook bekend as perlemoen) is die grootste van vyf inheemse spesies wat langs die kus van Suid-Afrika aangetref word. Dit is die enigste spesie van kommersiële waarde wat bydraend is tot die uitbuiting van hierdie diere. As gevolg van die afname in hierdie natuurlike hulpbron het boerdery praktyke gedurende die vroeë 1990's ontstaan om in die internasionale aanvraag te voorsien. Ten einde doeltreffende teelmetodes te beoefen en die volhoubaarheid van hierdie kommersiële populasies te verseker is genetiese bestuur, wat bewerkstellig kan word deur die gebruik van molekulêre merkers soos enkel nukleotied polimorfismes (ENPs), baie belangrik. Enkel nukleotied polimorfismes is gewilde merkers in verskeie toepassings in akwakultuur genetika as gevolg van hul oorvloed in genome, verlaagde ontwikkelingskoste en verhoogde deurset van ENP-genotiperingstoetse. Identifisering van ENPs in nie-model spesies soos H. midae kan uitgevoer word deur in siliko benaderings te gebruik wat geskik is vir de novo ENP identifisering en ook tyd- en koste-effektief is. Dit word gebaseer op die analise van veelvuldige inlynstellings waar nukleotiedes wat nie ooreenstem nie as kandidaat ENPs gerapporteer kan word. Om kandidaat ENPs te bevestig, kan verskeie medium-deurset genotiperingsmetodes uitgevoer word, maar die ideale metode word bepaal deur faktore soos koste, akkuraatheid en multipleks kapasiteit. Alhoewel ENP merkers in verskeie toepassing binne die akwakultuur omgewing gebruik kan word was die fokus van die huidige studie om die koppelingskaart van H. midae te versadig. Dit sal bydrae tot die identifisering van kwantitatiewe eienskap lokusse wat gekoppel kan word aan ekonomies belangrike eienskappe wat dan op die beurt weer vir merkerbemiddelde seleksie gebruik kan word en uiteindelik ten opsigte van die verbetering van molekulêre teelprogramme aangewend kan word. Ten einde in siliko ENPs te identifiseer is transkriptoomdata van 'n vorige studie gebruik en onderwerp aan 'n reeks kriteria: geringste alleelfrekwensie 10%, minimum dekking 80, 60 bp gebiede weerskante van polimorfisme. Geïdentifiseerde lokus-genotipering is met behulp van 'n 192-pleks toets uitgevoer met die Illumina GoldenGate genotiperingstoets met die VeraCode tegnologie op die BeadXpress-platform, in individue afkomsitg vanaf ses karteringsfamilies. 'n Omskakelingskoers van 69.35% en 'n algehele sukseskoers van 76.34% is bereik. Polimorfiese lokusse is onderwerp aan koppelings-analise met behulp van JoinMap® v.4.1 om geslags-gemiddelde en geslags-spesifieke kaarte te skep asook om die kaart wat beskikbaar is vir H. midae te versadig. Saam met voorheen ontwikkelde merkers is 54% van die nuut ontwikkelde ENPs suksesvol opgeneem in die kaart van H. midae. 'n Totaal van 18 koppelingsgroepe is verkry met 'n gemiddelde merker-spasiëring van 6.9 cM en 'n genoomdekking van 79.1%. Die gebruik van bioinformatiese analises en streng kriteria om ENPs vanaf transkriptoomdata te identifiseer blyk doeltreffend te wees in hierdie studie. Genotipering van die geïdentifiseerde lokusse met die GoldenGate genotiperingstoets dui op 'n hoë suksessyfer en verskaf 'n voldoende genotiperingstoets aan spesies met min genomiese inligting. Die koppelingskaart in hierdie studie het geïllustreer dat die ENP merkers suksesvol saam met mikrosatelliet merkers gebruik kan word vir koppelingskaart konstruksie en dat die voldoende merker-spasiëring verkry 'n stap nader aan kwantitatiewe eienskap lokus kartering in hierdie spesie bied.
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Boersma, Jeffrey George. "Contributions to the molecular genetics of the Narrow-leaf Lupin (Lupinus augustifolius L.) : mapping, marker development and QTL analysis." University of Western Australia. School of Earth and Geographical Sciences, 2007. http://theses.library.uwa.edu.au/adt-WU2008.0001.
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[Truncated abstract] Narrow-leaf lupin (Lupinus angustifolius L.) was first recorded as having been introduced into Germany during the mid-19th century for use as green manuring and as fodder crops. However, it was not until post World-War I that there was any serious attempt to domesticate the species. Since that time several key domestication genes have been incorporated to enable the species to be grown as a crop over a range of climates, harvested as a bulk commodity and, the seed used for both animal and human consumption. However, the recent domestication of this species has seen a rather limited use of wild germplasm largely as a result of the difficulty in retaining these key domestication genes. To make the task of retaining these genes manageable, it was decided to resort to molecular technology. A mapping population of F8 derived recombinant inbred lines (RILs) has previously been established by the Department of Agriculture and Food, Western Australia, from a cross between a domesticated breeding line 83A:476 and a wild type P27255 in narrow-leaf lupin. The parents together with 89 RILs (of a population of 115) were subjected to DNA fingerprinting using microsatelliteanchored fragment length polymorphism (MFLP) to rapidly generate DNA markers for construction of a linkage map. Five hundred and twenty two unique markers of which 21% were co-dominant, were generated and mapped. Phenotypic data for the domestication traits: mollis (soft seeds), leucospermus (white flower and seed colour); Lentus (reduced pod-shattering), iucundis (low alkaloid), Ku (early flowering) and moustache pattern on seed coats; were included. Three to 7 molecular markers were identified within 5 cM of each of these domestication genes. The anthracnose resistance gene Lanr1 was also mapped. Linkage groups were constructed using MapManager version QTXb20, resulting in 21 linkage groups consisting of 8 or more markers. ... Five pairs of QTLs were found to be involved in epistasis, 2 of these having an effect on early vigour and another 3 influencing the time to opening of the first florets. Variation explained for each trait ranged from 28% for seed size, to 88% for days to flowering. We showed that it was possible to use this data to predict genotypes of superior progeny for these traits under Mediterranean conditions. QTL regions were compared on a second published linkage map and regions of conserved synteny with the model legume Medicago truncatula high-lighted. The work presented in this thesis demonstrates the importance of tight linkage between markers and genes of interest. It is especially important when dealing with genetically diverse material as found in the wild. One of the main problems faced by molecular scientists is the phenomenon known as linkage disequilibrium in marker populations caused by either small population size or 4 insufficient opportunity for recombination. This frequently results in the development of markers with little or no application outside of the population in which it was developed. Although the relatively small size of the population used in this study exposes it to such constraints, in this case excellent and valuable results were achieved in developing useful markers to at least 3 of the domestication traits within a relatively short time period of less then 4 years.