Дисертації з теми ""cytogenetic markers""

UVOD Prenatalna dijagnostika predstavlja skup metoda i postupaka čiji je cilj da potvrde ili isključe postojanje kongenitalnih anomalija ploda. Prenatalni skrining može biti ne invazivni i invazivni. Ne invazivni skrining treba da ima visku senzitivnost i da omogući adekvatnu selekciju trudnica kojima će se predložiti genetsko ispitivanje ploda iz uzoraka dobijenih invazivnim metodama prenatalne dijagnostike. Prenatalni skrining prvog trimestra trudnoće obuhvata ultrazvučni pregled debljine nuhalne translucencije i laboratorijsku analizu dva biohemijska markera od 11 do 14 nedelje trudnoće, Prenatalni skrining drugog trimestra trudnoće koji se zasniva na biohemijskom skriningu i tripl testu iako je jedini koji se primenjuje zbog niske senzitivnosti od 20% do 40%, ne može se smatrati validnim. Integrativni biohemijski test prvog i drugog trimestra imaj veću senzitivnost (od 40 do 60%) ali ni on nije dao očekivane rezultate u adekvatnoj selekciji trudnica za genetsku analizu ploda zbog visoke stope lažno pozitivnih rezultata. Drugi trimestar trudnoće omogućava sonografskim pregledima i biohemijskim analizama dopunski način a u nekim slučajevima i jedini u proceni postojanja rizika Daunovog sindroma ili nekih drugih hromozomskih aberacija ploda Zato je primena integrativnih prenatalnih ne invazivnih metoda prvog i drugog trimestra trudnoće veoma značaja u poboljšanju dijagnostičkih vrednosti prenatalnih skrining testova i ima za cilj da smanji procenat invazivnih procedura zbog mogućih komplikacija i ne potrebnih finansijskih troškova. Daunov sindrom(trizomija 21 para hromozoma) je najčešća hromozomska numerička aberacija praćena mentalnom retardacijom dece (I.Q<70. ) Deca sa Daunovim sindromom su karakterističnog fenotipskog izgleda i sa čestim kongenitalnim anomailjama koje im onemogućavaju normalan život a često su i uzrok njihove prerane smrtnosti. Kongenitalne anomalije su zastupljene kod 2% do 5% živo rođene dece, predstavljaju 25 % perinatalne smrtnosti, četvrtina su uslovljnene hromozomskim aberacijama ili naslednom osnovom, od čega 0, 2%-0, 4% su sa Daunovim sindromom. CILJEVI Ciljevi četrorogodišnjeg istraživanja su bili da se poboljša dijagnostička vrednost postojećih prenatalnih testova, da se potvrdi značaj ultrazvučnog skrininga drugog trimestra trudnoće analizom debljine vratne brazde i dužine butne kosti ploda te da se poboljša njegova senzitivnost korporativnom sonografskom analizom cefaličnog indexa, intraorbitalnog rastojanja i dužine fronto-talamične distance. MATERIJAL I METODE Ukupan broj trudnica obuhvaćen četvorogodišnjim ispitivanjem koje su ultrazvučno pregledane i kojima je savetovano genetsko ispitivanje ploda blio je 4552. Tokom Retrospektivnog dvogodišnjieg ( 2010.2011)bila je 2169 dok je prospektivnom dvogodišnjom analizom (2012, 2013)je bilo obuhvaćeno 2383 trudnica. Ispitivana grupa su bile trudnice kod kojih je genetskom analizom otkriven patološki kariotip ploda, kontrolna grupa je obuhvatila sve ostale trudnice kod je kariotip ploda bio normalan od kojih su 124 trudnice odabrane metodom slučajnog izbora. Retrospektivnom studijom ultrazvučna je pregledana dužina vratne brazde(>6mm i dužina butne kosti<0, 6 od 14 do 22 nedelje trudnoće. Analizirana je cirkulacija fetalne krvi kroz duktus venosus ploda( a talas) i postojanje nosne kosti ploda(+, -). Prospektivnom analizom je ultrazvučnim pregledom ploda dodatno analiziran cefalični index(>85%), i intraorbitalna distanca i duzina fronto-talamične distance(<80%) ploda. Korišćene su metode deskriptivne statističke analize, aritmetička sredina, standardna devijacija, najmanja i najveća vrednost kod parametrijskih obeležja dok su za ne parametrijska postojanje nosne kosti i alfa talasa duktusu venozusu korišćene druge statističke metode, a komparativnim statističkim metodama kod normalnih, patoloških i kariotipova sa Daunovim sindromom ploda. Statistička značajnost je dokazana t testom a definisana nivoom p<0, 05 i p<0, 001 odnosom kod normalnih, patoloških kariotipova i Daunovog sindroma. Multifaktorskom regresivnom logističkom analizom je urađena procena senzitvnosti prenatalnog ultrazvučnog skrininga sa ispitivanim obeležjima drugog trimestra trudnoće REZULTATI I DISKUSIJA Od ukupnog broja ultrazvučno pregledaninh trudnica 4552 kojima je savetovano genetska analiza ploda citogenetskom analizom je otkriveno 66 patoloških kariotipova 1, 49%, sa Dunovim sindromom 31 0, 68%. Deskriptivnom statističkom obradom ultrazvučno ispitivanih obeležja od 14 do 22 nedelje trudnoće, uočeno je odstupanje i potvrđen značaj starije životne dobi trudnica, debljine vratne brazde i dužine frontotalamične distance u odnosu na normalne nalaze katiotipova ploda u predikciji Daunovog sindroma.Vrednosti dužine butne kosti, cefaličnog indeksa i intraorbitalnog rastojanja nisu imala veća odstupanja u poređenju patoškokih i normalnih nalaza kariotipova.Studentovim t testom je i dokazano p<0, 001 za debljinu vratne brazde i dužinu fronto-talamične distance, dok je za stariju životnu dob trudnice potvrđeno a;0, 001. Senzitivnost prenatalnog skrininga drugog trimestra analizom debljine vratne brazde i dužine butne kosti je veća u odnosu na standardno primenjivan biohemijski skrining drugog trimestra tripl testa (senzitivnost 40%-60) sa velikom stopom lažno pozitivnih rezultata.Dokazan je značaj poboljšanja senzitivnosti prenatalnih skrining testova dopunskom analizom tri ultrazvučna parametra, dužine fronto-talamične distance, cefaličnog indeksa i intraorbitalnog rastojanja u predikciji Daunovog sindroma, ali i kod ostalih hromozomskih aberacija ploda u periodu od 14 do 22 nedelje trudnoće primenomi multifaktorske logističke regresivne analize senzitivnost preko 93% sa 7% lažno pozitivnih rezultata. Postojanje korelacije između debljine vratne brazde i dužine fronto-talamične distance ploda poboljšavai senzitivnost prenatalnih ultrazvučnog skrininga. Integrativnim pristupom ultrazvučnog i biohemijskog skrininga drugog trimesra trudnoće, tripl testa očekuje se poboljšati dijagnostičkih vrednosti prenatalnog skrininga senzitivnost ne invazivnog skrininga u predikciji Daunovog sindroma i ostalih hromozomskih aberacija ploda. ZAKLJUČCI 1Potvrđen je značaj starije životne dobi trudnice u povećanju rizika Daunovog sindoma, i ostalih hromozomskih aberacija ploda ( p<0, 001) Potvrđen je značaj zadebljanja vratne brazde ploda >6mm(p<0, 001) i skraćenja butne kosti kod Daunovog sindroma ploda od 14 do 22 nedelje trudnoće u prenatalnom otkrivanju Dunovog sindroma i ostalih hromozomskih aberacija ploda i selekciji trudnica kojima će se predložiti genetsko ispitivanje ploda.Potvrđena je hipoteza da skraćenje fronto-talamične distance poboljšava senzitivnost ultrasonografskog skrininga, jer češće postoji kod Daunovog sindroma ploda ali i ostalih numeričkih hromozomskih aberacija tipa, nego kod normalnih nalaza kariotipa ploda( p<0, 001).Komparativnom analzom ultrazvučnim pregledom fronto-talamična distance debljine vratne brazde i dužine butne kosti ploda od 14 do 22 nedelje trudnoće može se značajno poboljšati vrednost dijagnostičkih prenatalnih testova u predikciji Daunovog sindroma. Postojanje korelacija između fronto-talamične distance i debljine vratne brazde dopunjuje ultrazvučni skrining i povećava njegovu senzitivnost na preko 90%, što je multifaktorskom regresivnom logaritamskom analizom i potvrđeno. Značaj multidisciplinarnog pristupa pogotovo je izražen u predikciji Daunovog sindroma, obzirom na različite specijalnosti koje u njemu učestvuju. Cost – benefit analiza. Visoka senzitivnost ne invazivnog prenatalnog skrininga u predikciji Daunovog sindroma, smanjuje troškove za pojedince i državu jer je njihova cena i do dest puta manja od cene citogenetskih analiza, a i trudnice se ne izlažu riziku mogućih komplikacija prilikom izvođenja invazivnih metoda
INTRODUCTIONS Prenatal diagnostic procedure represent a set of methods and techniques with the aim to afirmate or eliminate the presence of Down’s syndrome and other congenital anomalies Can be non-invasive and invasive methods. Non-invasive methods (laboratory or ultrasonographic) have the aim to make possible the most valid assessment of the risk of presence of an affected fetus in the pregnancy, selected pregnancy for invasive diagnostics procedures and citogenetics analisseskariotipingfoeti. Down’s syndrome, aneuploidy with trisomy 21 chromosomal, is the most common chromosomal numerical aberration associated with mental retardation of children (IQ< 70). Children with Down’s syndrome have characteristic phenotypic appearance with high frequent congenital anomalies that preclude a normal life and are frequently the cause of their earlier death. AIM The aim of the four year long investigation was to confirm the importance of ultrasound screening by the analyses of the basic ultrasound parameters for the second trimester, the thickness of the nuchal fold and the length of the femur of the fetus in the prediction of Down’s syndrome and other chromosomal aberrations of the fetus, as well as to improve other existing ultrasonic screenings of the first and second trimester of pregnancy by ultrasonic examination and analyses of the cephalic index and intraorbital space and the length of the fronto-thalamic distance. MATERIAL AND METODS Retrospective investigation (2010. 2011) and prospective investigation (2012.2013) includes 4655 pregnant women. For all pregnant women the genetic investigation of the fetus was performed. A total of 68 were found with chromosomal aberrations, 38 with Down’s syndrome. The method of haphazard choice in retrospective study and in prospective study ultrasound markers are examined. In retrospective analyses of the nuchal fold (<6mm and the length of femur <0.6, that represent basic ultrasound screening of the second trimester and are analyzed as parametric signs of the second trimester, and are analyzed as parametric markers, and analyses of the circulation of fetal blood through ductus venosus of the fetus. In the retrospective study the length of the nuchal fold (>6mm in length, that represent a basic ultrasound screening of the second trimester, and are analyzed as parametric markers in the prediction of Down’s syndrome and other chromosomal aberrations. RESULTS AND DISCUSION Cytogenetic analyses revealed 66 (1, 49%) pathologic karyotypes and Down syndrome were present in 31 (0, 68%) cases. All pathologic karyotypes were obtained after ultrasound examinations of 4552 pregnant women. Ultrasound markers for period 14th-22nd GW were analyzed with descriptive statistical methods and importance of pregnancy in older women, thickness of nuchal fold and lengths frontal thalamic distance were proofed in case of Down syndrome. Femoral bone lengths, cephalic index and intraorbital distances were similar for both groups, normal and pathologic karyotypes. Student’s t test revealed statistical significance with p<0, 001 values for nuchal fold thickness, frontal thalamic distance and older ages.Three additional ultrasound markers (frontal thalamic distance, cephalic index, intraorbital distance) improve prediction of Down syndrome and other chromosomal aberrations between 14th and 22nd GW as well. Multifactorial logistic regressive analyses revealed 93% sensitivity with 7% false positive results. Corelation between nuchal fold thickness and frontal thalamic distance improve prenatal ultrasound screening sensitivity. Using both ultrasound and biochemical screening (triple test) is way to improve sensitivity of non invasive screening in prediction of Down syndrome and other chromosomal aberrations. CONCLUSIONS Importance of pregnant women ages and higher risk for Down syndrome and other chromosomal aberrations was proofed (p<0, 001).Importance of nuchal fold thickness above 6mm (p<0, 001) and shorter femoral bone marker in period from 14th to 22nd GW in prediction of Down syndrome and other chromosomal aberrations are proofed (p<0, 001). Hypothesses that frontal thalamic distance improve ultrasound screening sensitivity was proofed was proofed (p<0, 001) since it is significantly shorter in Down syndrome and other chromosomal aberrations in comparison with fetuses with normal karyotypes. Comparative analyses of frontothalamic distance, nuchal fold thickness and femoral bone length in period from 14th to 22nd GW can signifi cantly improve prenatal diagnostic testing in Down syndrome prediction. Correlation between frontothalamic distance and nuchal fold thickness improve ultrasound screening sensitivity on 93% that is proofed with multifactorial logistic regressive analyses. Significance of multidisciplinary approach is high in Down syndrome prediction. Cost-benefit: High sensitivity of non invasive prenatal screening in Down syndrome prediction reduces costs for families and government since it costs ten time less than cytogenetic analyses and risk with invasive procedures is avoided.

Genetic resistance to Wheat streak mosaic virus (WSMV) offers the most attractive and environmentally safe strategy for disease control. While effective resistance in hexaploid bread wheat (Triticum aestivum) has recently been described in only one case, the Wsm2 gene, more successful resistance has been introgressed from the related hexaploid wheatgrass, Thinopyrum intermedium, as the Wsm1 and Wsm3 genes. In the current study, fluorescent in situ hybridization (FISH) with genomic DNA from Th. intermedium, Aegilops tauschii and repetitive DNA probes was applied to four breeding populations of wheat-Th. intermedium, previously tested for WSMV-resistance. Three different wheat-Th. intermedium recombinant chromosomes, the well-known 4Ai#2S.4DL and two novel, 1B and 3D, were identified to be associated with WSMV-resistance. These novel introgressed genes from Th. intermedium were designated as Wsm4 and Wsm5 respectively. The Wsm4 gene was pinpointed to a 6% interstitial map region on the 1BS flanked by Xgwm4144 and Xgwm1100 markers. Six new PCRmarkers, five linked to Wsm1 and one to Wsm4 were identified. Molecular markers now provide a good coverage of the 4Ai#2S arm for effective marker assisted selection and the new genes increase our arsenal to combat the disease. Two highly repetitive satellite DNA families, Afa and pSc119.2, were isolated for the first time from Th. intermedium and their diversity in respect to copies from other Triticeae species were investigated. They showed contrasting evolutionary dynamics leading to time dependent or independent homogenization of Afa and pSc119.2 sequences. Both repeats are excellent cytological markers and characterized the 4Ai#2S chromosomal arm, in the alien wheat lines and the Th. intermedium genome. Southern hybridization, with methylation sensitive and insensitive restriction enzymes and immunostaining with anti-5-methyl-cytosine antibodies were employed to assess DNA methylation. Overall, no massive changes were evident in the wheat genome, however the alien arm showed reduced cytosine methylation which is characteristic for actively transcribing chromatin.

DNA markers tightly-linked to nuclear fertility restorer genes for cytoplasmic male sterility (CMS) are valuable tools for breeders and researchers working with these genes. Two different targeting approaches were used to identify markers linked to the Rfp1 restorer gene for the pol CMS of canola (Brassica napus L.): nearly isogenic line (NIL) comparison and bulked segregant analysis. These methods were equally efficient in identifying markers linked to Rfp1; combining them allowed a targeting efficiency of 100% to be achieved. The efficiency of bulked segregant analysis was found to be limited by the inadvertent occurrence of shared homozygosity at specific chromosomal regions in the bulks, in contrast with the efficiency of NIL comparison which was limited by the occurrence of residual DNA from the donor cultivar at scattered sites around the genome of the NILs. Eleven DNA markers linked to the Rfp1 gene were identified, one of which perfectly co-segregates with Rfp1. The linkage group on which Rfp1 is localized contains 17 DNA markers. Two restorer genes of the pol CMS, Rfp1 and Rfp2, and a Rfn restorer gene of the nap CMS were found to be at least tightly linked to one another and may all reside at the same locus. A fourth restorer gene, the Rfo restorer for the ogu CMS, was, however, found to be unlinked to the other restorer genes. Different restorer genes for the nap CMS were found in the lines 'Westar-Rf and 'Karat'. A linkage map of the B. napus genome containing 146 markers organized into 23 linkage groups covering a total length of 850.2 cM was constructed from a BC$ sb1$ population. This map contains 63 loci previously localized on the B. napus genome through analysis of an F$ sb2$ population. Comparative analysis indicates that the total length of the BC$ sb1$-derived map is smaller than that of the F$ sb2$-derived map, which suggests that a reduction in recombination frequency is occurring in male gametes. The preferential use of two or three probe-

A two-component transposable element system consisting of a stabilized Activator (Acst) and a chimeric Dissociation (Ds) element has been introduced into the genome of Brassica napus. This Acst/ Ds system incorporates the use of several highly effective screenable and selectable markers. One of these markers is the maize Lc gene, a transcriptional regulator of flavonoid biosynthetic genes. This substrate-independent screenable marker was tested for the first time in B. napus and I show that when overexpressed, there is augmented trichome production and a light-dependent, enhanced accumulation of anthocyanins in B. napus plants. The phenotypes are expressed under a wide range of conditions, are visually distinct, and are observed throughout plant development. When used as a visual marker for the Acst element, Lc B. napus plants were rapidly identified among F2 segregating populations. As part of my goal to develop a very efficient Acst/Ds system for use in B. napus, a conditional negative selectable marker, the E. coli codA gene, was also tested for the first time in B. napus. This was done because use of a substrate-dependent negative selectable marker can facilitate the rapid and reliable identification of stable Ds transposition events when used as a marker for the Acst T-DNA. The enzyme cytosine deaminase, encoded by the codA gene, catalyzes the deamination of the non-toxic compound 5-fluorocytosine (5-FC) to the highly toxic compound 5-fluorouracil. In codA transformed B. napus seedlings, expression of cytosine deaminase results in a severe suppression of growth and this phenotype is dependent on the presence of the 5-FC substrate. Wild-type seedlings, however, lack endogenous cytosine deaminase activity and appear unaffected by the presence of 5-FC in the growth media. These results indicate that codA has the potential to be used effectively in B. napus as a substrate-dependent negative selectable marker for the Acst T-DNA. To determine if Ac transposase cou

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A hibridação artificial interespecífica de peixes é utilizada em diversos estabelecimentos voltados à piscicultura no país, com a finalidade de produzir indivíduos mais vantajosos e favoráveis para o cultivo. Porém, devido principalmente às dificuldades encontradas na identificação dos híbridos, esta prática pode determinar o surgimento de sérios problemas como a contaminação genética dos estoques de cultivo, a comercialização de produtos híbridos como espécies puras, a introdução de espécies exóticas e escapes de produtos de piscicultura para o ambiente natural e até eventos de introgressão genética e extinção das espécies nativas. Neste contexto, o presente trabalho teve por objetivo analisar geneticamente exemplares das linhagens parentais de Pseudoplatystoma corruscans (pintado) e Pseudoplatystoma reticulatum (cachara) e seus híbridos interespecíficos pintachara (macho de pintado x fêmea de cachara) e cachapinta (fêmea de cachara x macho de pintado), provenientes dos estoques de cultivo do CEPTAlICMBio, Pirassununga, SP, a fim de identificar e estabelecer marcadores genéticos para possibilitar sua identificação e diferenciação. Também foram analisadas geneticamente amostras de P. corruscans e P. reticulatum coletadas no Rio Paraguai, MS (bacia do Paraguai) e de P. corruscans capturados do rio Mogi- Guaçu, SP (bacia do Alto Paraná), a fim de identificar a possível ocorrência de híbridos entre estas espécies na natureza. As análises citogenéticas revelaram um número diploide de 2n=56 cromossomos para ambas as espécies parentais, com cariótipos caracterizados por cromossomos dos tipos 20m+12am+12st+12a e número fundamental (NF) igual a 100, indicando uma fórmula cariotípica conservada entre estas espécies. A análise dos padrões de heterocromatina pelo bandamento C revelou blocos heterocromáticos localizados nas porções...
Artificial interspecific hybridization of fish is used in various establishments linked to fish farming in the country, in order to produce individuais more advantageous and favorable for cultivation. However, due mainly to difficulties in the hybrid products identification, this practice may determine the onset of serious problems such as genetic contamination of the breeder stocks, marketing of hybrids as pure species, introduction of exotic species and escapes of farmed products to the natural environment and sometimes leading to events of genetic introgression and extinction of native species. In such context, the present study aimed to analyze genetically copies of the parental lines of Pseudoplatystoma corruscans (pintado) and Pseudoplatystoma reticulatum (cachara) and their interspecific hybrids pintachara (female of pintado x male of cachara) and cachapinta (female of cachara x male of pintado), from the stocks manteined in CEPTAlICMBio, Pirassununga, SP, in order to characterize and establish genetic markers to allow their identification and differentiation. Samples of P. corruscans and P. reticulatum collected in the Paraguay river, MS (Paraguay basin) and P. corruscans captured in Mogi-Guaçu river, SP (Alto Paraná basin), also were genetically analyzed in order to identify the possible occurrence of hybrids between these species in nature. The cytogenetic analysis revealed a diploid number of 2n = 56 chromosomes for both parental species with karyotypes characterized by the formula 20m+12am+12st+12a and fundamental number (NF) of 100, indicating a karyotypic formula conserved among these species. The analysis of the heterochromatin C-banding patterns revealed heterochromatic blocks located in the pericentromeric and terminal portions of some chromosomes, the NOR was sim pie and located in one chromosome pai r and 5S ribosomal genes located on two different subtelocentric... (Complete abstract click electronic access below)

Orientador: Fábio Porto Foresti
Banca: José Augusto Senhorini
Banca: Celso Benites
Resumo: A hibridação artificial interespecífica de peixes é utilizada em diversos estabelecimentos voltados à piscicultura no país, com a finalidade de produzir indivíduos mais vantajosos e favoráveis para o cultivo. Porém, devido principalmente às dificuldades encontradas na identificação dos híbridos, esta prática pode determinar o surgimento de sérios problemas como a contaminação genética dos estoques de cultivo, a comercialização de produtos híbridos como espécies puras, a introdução de espécies exóticas e escapes de produtos de piscicultura para o ambiente natural e até eventos de introgressão genética e extinção das espécies nativas. Neste contexto, o presente trabalho teve por objetivo analisar geneticamente exemplares das linhagens parentais de Pseudoplatystoma corruscans (pintado) e Pseudoplatystoma reticulatum (cachara) e seus híbridos interespecíficos "pintachara" (macho de pintado x fêmea de cachara) e "cachapinta" (fêmea de cachara x macho de pintado), provenientes dos estoques de cultivo do CEPTAlICMBio, Pirassununga, SP, a fim de identificar e estabelecer marcadores genéticos para possibilitar sua identificação e diferenciação. Também foram analisadas geneticamente amostras de P. corruscans e P. reticulatum coletadas no Rio Paraguai, MS (bacia do Paraguai) e de P. corruscans capturados do rio Mogi- Guaçu, SP (bacia do Alto Paraná), a fim de identificar a possível ocorrência de híbridos entre estas espécies na natureza. As análises citogenéticas revelaram um número diploide de 2n=56 cromossomos para ambas as espécies parentais, com cariótipos caracterizados por cromossomos dos tipos 20m+12am+12st+12a e número fundamental (NF) igual a 100, indicando uma fórmula cariotípica conservada entre estas espécies. A análise dos padrões de heterocromatina pelo bandamento C revelou blocos heterocromáticos localizados nas porções... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Artificial interspecific hybridization of fish is used in various establishments linked to fish farming in the country, in order to produce individuais more advantageous and favorable for cultivation. However, due mainly to difficulties in the hybrid products identification, this practice may determine the onset of serious problems such as genetic contamination of the breeder stocks, marketing of hybrids as pure species, introduction of exotic species and escapes of farmed products to the natural environment and sometimes leading to events of genetic introgression and extinction of native species. In such context, the present study aimed to analyze genetically copies of the parental lines of Pseudoplatystoma corruscans (pintado) and Pseudoplatystoma reticulatum (cachara) and their interspecific hybrids "pintachara" (female of pintado x male of cachara) and "cachapinta" (female of cachara x male of pintado), from the stocks manteined in CEPTAlICMBio, Pirassununga, SP, in order to characterize and establish genetic markers to allow their identification and differentiation. Samples of P. corruscans and P. reticulatum collected in the Paraguay river, MS (Paraguay basin) and P. corruscans captured in Mogi-Guaçu river, SP (Alto Paraná basin), also were genetically analyzed in order to identify the possible occurrence of hybrids between these species in nature. The cytogenetic analysis revealed a diploid number of 2n = 56 chromosomes for both parental species with karyotypes characterized by the formula 20m+12am+12st+12a and fundamental number (NF) of 100, indicating a karyotypic formula conserved among these species. The analysis of the heterochromatin C-banding patterns revealed heterochromatic blocks located in the pericentromeric and terminal portions of some chromosomes, the NOR was sim pie and located in one chromosome pai r and 5S ribosomal genes located on two different subtelocentric... (Complete abstract click electronic access below)
Mestre

Gelasine Herb. (Tigridieae: Iridaceae) é composto por sete espécies nativas da América do Sul, sendo três delas encontradas no Rio Grande do Sul (Brasil): G. coerulea (Vell.) Ravenna, G. elongata (Graham) Ravenna e G. uruguaiensis Ravenna. São plantas bulbosas de folhas plicadas, flores perfeitas azuis ou roxas e compostas por dois conjuntos de tépalas desiguais. Gelasine elongata e G. coerulea encontram-se na lista de espécies ameaçadas para o RS, sendo a primeira delas ameaçada e a segunda criticamente ameaçada. Apesar de seu atual estado de vulnerabilidade, Gelasine é um gênero ainda pouco estudado, não havendo nenhuma informação quanto à variabilidade e diversidade genética. Os dados citogenéticos são também ainda escassos. Assim, a presente dissertação tem por objetivo caracterizar as três espécies de Gelasine ocorrentes no sul do Brasil quanto a aspectos moleculares, citogenéticos, além de compreender suas relações. Para a caracterização da diversidade genética foram usadas duas populações de G. coerulea e duas de G. elongata; não foi possível a utilização de G. uruguaiensis em função do número restrito de indivíduos. As amostras de DNA foram obtidas a partir de folhas das espécies mencionadas e empregada a técnica de ISSR (Inter Simple Sequence Repeat). Foram testados 44 primers para ISSR, destes, 12 apresentaram um bom padrão de amplificação que em conjunto geraram 91 loci. A quantidade de bandas por primer variou em média de 7,5. Este trabalho resultou em dados inéditos para o gênero Gelasine quanto à variabilidade genética inter e intra-populacional. Os resultados indicam que a variação genética intrapopulacional é muito baixa e que a maior diversidade encontrada para estas espécies ocorreu entre as populações. Não foi verificada correlação significativa com a distância geográfica entre as populações. Tais resultados indicam que o sistema reprodutivo, o método de dispersão de sementes e a presença de descendência clonal oriunda da divisão dos bulbos subterrâneos são fatores de grande influência na diversidade. Para caracterização citogenética das espécies foi empregada coloração convencional e bandeamento CMA/DAPI, e realizadas medidas cromossômicas. Foi também estimado o tamanho do genoma por citometria de fluxo a partir de folhas frescas das três espécies. As análises citogenéticas se mostraram bastante eficientes para a diferenciação das três espécies de Gelasine investigadas. Gelasine coerulea e G. uruguaiensis apresentam o mesmo número cromossômico básico e somático (2n = 2x = 14), não sendo encontrados citótipos poliploides. Ambas têm cariótipos relativamente simétricos, porém se mostram bastante distintas quanto ao tamanho dos cromossomos e seu padrão de bandeamento, com uma grande variação na ocorrência e distribuição de sequências de DNA repetitivo (bandas CMA/DAPI). O conteúdo de DNA também permite a clara diferenciação dessas espécies, tendo G. coerulea 2C = 11,30 pg e G. uruguaiensis 2C = 16,88 pg. Gelasine elongata possui número cromossômico básico diferente das anteriores (2n = 2x = 12) e cariótipo claramente bimodal. Os cromossomos têm menor tamanho, o que, consequentemente reflete no menor tamanho de genoma (2C = 3,45 pg). Além disso, o padrão de bandas CMA/DAPI é notadamente mais simples que das outras duas espécies, onde o maior par de cromossomos (par I) exibe as únicas bandas CMA+ presentes na região da constrição secundária. Os dados obtidos para G. elongata apontam para uma maior semelhança dessa espécie com outras duas do gênero Eleuthenine (2n = 2x = 12), o que reforça os dados filogenéticos existentes, onde G. elongata está separada de G. coerulea e agrupada no mesmo ramo de Eleutherine. Não foi observado heteromorfismo cromossômico para Gelasine elongata e nem para as outras duas espécies investigadas, embora tal situação tenha sido reportada para aquela espécie. Os dados obtidos para Gelasine com o uso dos fluorocromos CMA e DAPI, bem como os demais parâmetros citogenéticos investigados permitiram a clara diferenciação entre as espécies. Associados a uma abordagem filogenética, tais resultados auxiliam a compreensão das relações entre essas espécies e sua evolução.
Gelasine Herb. (Tigridieae: Iridaceae) comprises seven native species from South America, three of them are found in Rio Grande do Sul (Brasil): G. coerulea (Vell.) Ravenna, G. elongata (Graham) Ravenna and G. uruguaiensis Ravenna. These species are bulbous plants with plicate leaves and blue or violet perfect flowers which are composed of two unequal groups of tepals. Gelasine elongata and G. coerulea are included in the list of endangered species from RS, the first one is considered endangered and the latter, critically endangered. Notwithstanding its current vulnerability status, Gelasine is still a poorly studied genus and genetic variability and diversity information concerning its species are lacking. Cytogenetic data are also scarce. Thus the present dissertation aims to characterize the three Gelasine species occurring in Southern Brazil regarding its molecular and cytogenetic aspects in addition to understand their relationships. To characterize their genetic diversity, two populations of G. coerulea and two of G. elongata were used; it was not possible to investigate G. uruguaiensis due to its restricted number of individuals. DNA samples were obtained from leaves of the aforementioned species and ISSR (Inter Simple Sequence Repeat) technique was employed. Fourty-four ISSR primers were tested, 12 of these presented good amplification pattern which generated a total of 97 loci. The number of bands per primer had an average of 7.5. The present study resulted in novelty data for Gelasine concerning its inter and intrapopulation genetic variability. The results indicate a very low intrapopulation genetic variation and most of the diversity found in these species occurred among their populations. No significant correlation was verified between geographical distances of populations. Such results indicate that reproductive system, seed dispersal mechanisms and presence of clonal descendants generated from divisions of subterranean bulbs are factors that greatly influence in diversity. For cytogenetic characterization of the species, conventional staining and CMA/DAPI banding were employed and chromosome measurements were made. Also, genome size was estimated through flow cytometry using fresh leaves from the three species. Cytogenetic analyses were very efficient to differentiate all investigated species of Gelasine. Gelasine coerulea and G. uruguaiensis have the same basic and somatic chromosome number (2n = 2x = 14); polyploid cytotypes were not found. Both species display fairly symmetric karyotypes, however they are very distinct with respect to chromosome sizes and banding patterns, with a great variation in the occurrence and distribution of repetitive DNA sequences (CMA/DAPI bands). DNA content also allows clear differentiation of these species; G. coerulea has 2C = 11,30 pg and G. uruguaiensis has 2C = 16,88 pg. Gelasine elongata has a different base chromosome number than both former species (2n = 2x = 12) and a clearly bimodal karyotype. Its chromosomes are smaller which, consequently, reflects on the smaller genome size (2C = 3,45 pg). Furthermore, its CMA/DAPI band pattern is markedly simpler than the ones from the other two species, where the largest chromosome pair (pair I) contains the only CMA+ bands present in the secondary constriction region. Data obtained from G. elongata points out a larger resemblance between this species and two others belonging to Eleuthenine (2n = 2x = 12), which supports the phylogenetic data where G. elongata is separate from G. coerulea and groups with Eleutherine. Chromosome heteromorphism was not observed in Gelasine elongata nor in the two other investigated species, even though it had been reported for the first one. Data obtained from Gelasine with the use of CMA and DAPI fluorochromes, along with the other cytogenetic parameters investigated, allowed clear differentiation between species. Allied to a phylogenetic approach, these results can bring better understanding to the relations between these species and their evolution.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Basic and molecular cytogenetic studies were carried out in Apareiodon affinis (Parodontidae) of five populations: Passa Cinco River, Ipeúna – SP; Piracicaba River, Piracicaba – SP; Paraná River (lake of the Itaipu dam - Santa Helena – PR) all belong to Upper Paraná River hidrografic system and; two localities of the Paraguay River drainage, Cuiabá River, Cuiabá - MT and, Paraguay River, Cáceres - MT. The conventional analysis showed that the three populations of the Upper Paraná River system have 2n = 54 chromosomes to males and 2n= 55 chromosomes to females. Those differences in the chromosome number are due to by presence of sex chromosome system showing female heterogamety ZZ/ZW1W2 type. The karyotypic formula and fundamental number (FN) for these three populations was 50 m/sm + 4 st. FN = 108 to males and; 49 m/sm + 6 st, FN = 110 to females. The sex chromosomes Z was characterized as the largest metacentric, while the chromosome W1 and W2 appears to be subtelocentrics and have half the size of the Z chromosome. In turn, the population of the Cuiabá River, Cuiabá – MT have 2n = 54 chromosome to males and females, karyotypic formula 42 m/sm + 2 st + 10 a and FN = 98 and; the Paraguay River population show 2n = 54 chromosomes and no heteromorphic sex chromosomes system and, karyotypic formula 36 m/sm + 2st + 16 a. Fluorescence in situ hybridizations (FISH) com 18S and 5S ribosomal DNAs were performed in the different populations of A. affinis, resulting in (i) a single metacentric chromosome pair bearing 5S rDNA sites for the samples on the Upper Paraná River, (ii) a heteromorphic situation of a chromosome metacentric and one acrocentric for the population of the Cuiabá River and; (iii) a acrocentric pair bearing 5S rDNA sites for the population of the Paraguay River. The 18S rDNA was found in the terminal region of the long arm of a subtelocentric pair in all populations. This situation is considered a sinapomorfic feature in Parodontidae when compared with the sister group Anostomidae. FISH with pPh2004 satellite DNA was also performed in all the populations of this study showing positive hybridization in differential sites: 3-4 pairs all m/sm in the Upper Paraná River samples and; 6-8 st/a pairs in the Paraguay River samples. Thus, the cytogenetic differences observed between Upper Paraná and Paraguay Rivers populations is possible to affirm the occurrence of a high karyotipic differentiation in gene flow restriction. Lower cytogenetic differentiation can be observed also when compared samples from the same river system. Thus, is possible to state that A. affinis of the Upper Paraná River population is divergent and should have their taxonomic condition reviewed.
Estudos citogenéticos básicos e moleculares foram realizados em cinco populações de Apareidon affinis (Parodontidae): Rio Passa Cinco, Ipeúna – SP; Rio Piracicaba, Piracicaba – SP; Rio Paraná (lago da represa de Itaipu – Santa Helena – PR) pertencentes ao sistema hidrográfico do Alto Rio Paraná e duas populações da bacia do alto Rio Paraguai, rio Cuiabá, Cuiabá - MT e rio Paraguai, Cáceres - MT. A análise convencional mostrou que nas três populações do sistema alto rio Paraná apresenta 2n = 54 cromossomos para machos e 2n = 55 cromossomos para fêmeas. Esta diferença de número cromossômico é resultado da presença do sistema de cromossomos sexuais múltiplo com heterogamia feminina, do tipo ZZ/ZW1W2. A fórmula cromossômica e número fundamental para estas três populações foi 50 m/sm + 4 st, NF = 108 para machos e; 49 m/sm + 6 st, NF = 110 para fêmeas. O cromossomo sexual Z é caracterizado por ser o maior cromossomo metacêntrico do complemento, enquanto os cromossomos W1 e W2 são subtelocêntricos com metade do tamanho do cromossomo Z. A população do rio Cuiabá, por sua vez, possui 2n = 54 cromossomos para machos e fêmeas, fórmula cromossômica 42 m/sm + 2 st + 10 a e; NF = 98 e a população do rio Paraguai não apresenta heteromorfismo de cromossomos sexuais e fórmula cariotípica 36 m/sm + 2 st + 16 a. Hibridização in situ fluorescente (FISH) com DNAs ribossomais 18S e 5S foram realizadas nas diferentes populações de A. affinis, resultando em apenas um par cromossômico metacêntrico marcado com DNAr 5S para as populações do Alto Rio Paraná, uma situação heteromórfica com um cromossomo metacêntrico e um acrocêntrico para a população do rio Cuiabá e; um par acrocêntrico para a população do rio Paraguai. O DNAr 18S foi localizado na região terminal do braço longo de um par cromossômico subtelocêntrico, de todas as populações estudadas podendo ser considerado uma característica sinapomórfica para a família, quando comparada com o grupo irmão Anostomidae. FISH com DNA satélite pPh2004 isolado de Parodon hilarii também foi realizada nas populações dos sistemas hidrográficos do alto rio Paraná e bacia do rio Paraguai, evidenciando hibridação positiva em sítios diferenciais: 3 – 4 pares marcados, todos m/sm com divergência populacional no Alto Rio Paraná e, 6 – 8 pares marcados, também com divergência para as populações do rio Paraguai, em sua maioria acrocêntricos. Assim, levando em consideração as diferenças cromossômicas entre Alto Rio Paraná e Rio Paraguai é possível afirmar a existência a de uma alta diferenciação cariotípica entre as populações dos diferentes sistemas hidrográficos em isolamento de fluxo gênico. Diferenciação menor também pode ser constatada quando comparadas as localidades de um mesmo sistema hidrográfico. Deste modo, é possível afirmar que as populações de A. affinis do Alto Rio Paraná são divergentes, possibilitando que sua condição taxonômica seja revista.

El establecimiento de correlaciones entre fenotipo y genotipo es uno de los principales objetivos de la genética. La obtención de un diagnóstico ajustado facilita el manejo clínico del paciente, así como poder ofrecer un correcto consejo genético, con asesoramiento reproductivo a las familias de pacientes con enfermedades genéticas. La identificación de genes asociados a patología desde alteraciones citogenéticas asociadas a fenotipo es uno de los métodos de clonación posicional. En este trabajo nos hemos basado en dos tipos de modelos de anomalías citogenéticas: balanceadas y no balanceadas (translocaciones y cromosomas marcadores). Hemos caracterizado las alteraciones citogenéticas de cinco pacientes de cada modelo con fenotipos diversos, empleando una combinación de técnicas citogenéticas y moleculares, con el objetivo de proponer genes candidatos asociados a cada fenotipo.
One of the main objectives of Genetics is the establishment of phenotype-genotype correlations. A correct diagnosis facilitates the clinical management of the patient and the possibility to offer a genetic counselling, with reproductive assessment to the families with a patient with a genetic disease. The identification of genes associated to pathology from cytogenetic alterations associated to phenotype is one of the methods of positional cloning. In this work we have based in two different models of cytogenetic alterations: balanced and unbalanced anomalies (translocations and marker chromosomes). We have characterized five patients of each group with different phenotypes, using a combination of cytogenetic and molecular techniques, with the objective of establish candidate genes associated to disease.

碩士
國立屏東科技大學
熱帶農業研究所
88
The purposes of this study are to evaluate genetic variation in Spathiphyllum germplasms based on morphological traits, RAPD markers, somatic embryogenesis and karyotype analysis. We examined morphological traits, such as leaf length, plant height and leaf numbers of 12 Spathiphyllum cultivars. The results showed that morphological traits were significantly different among cultivars. Both S. 'Max' and S. 'Sensation' were shown to be triploid with 2n = 45. Other cultivars, including S. 'Pallas', S. 'Luna', S. 'Ceres', S. 'Stephanie', S. 'Illusion', S. 'Vanessa', S. 'Domino', S. 'Jetty', S. 'Petite' and S. cannifolium were shown to be diploid with 2n = 30. Most genomes are with median type (m) and at least two pairs of submedian (sm) chromosomes, while two triploid cultivars having four pairs of submedian chromosomes. The karyotype of both S. 'Max' and S. 'Sensation' are 2n = 45 = 33m + 12sm . The karyotypes of other cultivars, including S. 'Luna', S. 'Petite', S. 'Jetty' and S. 'Stephanie' are 2n = 30 = 24 m + 6 sm, but the S. 'Petite' has secondary constriction in the 3rd chromosome. The karyotypes for S. 'Ceres', S. 'Domino', S. 'Vanessa', S. 'Illusion', S. 'Pallas' and S. cannifolium are 2n = 30 = 26 m + 4sm； however, S. cannifolium has a secondary constriction in 3rd chromosome. The ratio for longest and shortest chromosome is between 1.33 and 1.76. The centromeric terminalization value of chromosomes is 56.48-59.70 %, which shows high symmetry of karyotype in the genus. According to Stebbins (1971), karyotype for S. cannifolium was classified to 1A, while karyotypes of other cultivars were classified to 2A. Fourteen out of 95 random primers were selected in PCR reaction after preliminary screening. A total of 243 RAPD markers were amplified among these cultivars. Among them, 92 are cultivar specific, including 41 bands in S. cannifolium. Four bands are monomorphic for 12 cultivars, and 147 are polymorphic. Using UPGMA for dendrogram construction, S. cannifolium was shown to be most distant form other cultivars. All other cultivars can be subdivided into two groups with S. 'Max' and S. 'Sensation' in a group and others in the other group. Etiolated internode explants were cultured on 2,4-D and NOA containing MS media to induce somatic embryogenesis of S. 'Sensation'. The results showed that somatic embryos can be induced in these media except N2i and N2-m media. The frequency of somatic embryo formation rate was between 5.0%-26.7%. Callus formation rate was also between 47.5-82.5%. N2-n and N2-b media were used to compare somatic embryogenesis of six cultivars. The results showed that N2-n (0.1 mg/l 2,4-D and 0.02 mg/l) and N2-b (0.01 mg/l 2,4-D and 0.02 mg/l) media were able to induce somatic embryo formation of six cultivars. The somatic embryo formation rate was 25.0 % for S. 'Ceres', highest among six cultivars. Callus formation rate was between 10-50 %. On N2-b medium, embryo formation rate was 30.0 % for S. 'Enchantment', highest among six cultivars. Callus formation rate was between 12.5-62.5 %. Plantlets can be regenerated after transferring somatic embryos onto MS basal medium. Paraffin sections confirmed somatic embryo structure.

Dissertação de Mestrado em Genética Molecular Comparativa e Tecnológica
O núcleo alopoliplóide experiencia alterações genéticas e epigenéticas irreversíveis. A tribo Triticeae constitui um excelente taxon para estudar reestruturações genómicas em alopoliplóides recém-formados. O principal objetivo deste estudo foi verificar a ocorrência de potenciais reestruturações genéticas ao nível molecular e citogenético em tritordeuns (alopoliplóides H.chilense x T.turgidum) recém-formados por comparação com os respectivos progenitores. A natureza anfiplóide dos tritordeuns foi previamente confirmada por FISH. Realizou-se DNA fingerprint de duas linhas recém-formadas de tritordeum hexaplóide (HT22 e HT27) e respetivos progenitores utilizando os marcadores moleculares: IRAP, REMAP, ISSR e SCoT. Seis combinações de primers LTR e sete combinações de primers LTR e SSR produziram IRAPs e REMAPs, respetivamente. Dos 60 primers SCoT testados, apenas 18 amplificaram SCoTs na linha HT22 e 19 na linha HT27. Após análise de presença/ausência de bandas entre tritordeuns e respetivos progenitores, detetaram-se bandas polimórficas: i) comuns ao tritordeum e um dos progenitores, ii) amplificadas exclusivamente em tritordeum e/ou iii) específicas para um dos progenitores. Globalmente, todos os marcadores produzidos em tritordeum foram maioritariamente comuns ao progenitor trigo. As bandas polimórficas exclusivamente amplificadas em tritordeum (bem como as eliminadas), foram consideradas rearranjos genéticos derivados de alopoliploidização. Dos marcadores usados, os IRAP, REMAP e ISSR, foram melhor sucedidos na evidenciação de reestruturação genética em tritordeum. Ao nível citogenético foram testadas diferentes sondas SSR em esfregaços cromossómicos mitóticos de tritordeum recém-formado e respectivos progenitores através de ND-FISH. Apenas a sonda SSR (AG)10 revelou rearranjos estruturais nos cromossomas nucleolares 1B e 6B de tritordeum. Sucessivas experiências FISH com as sondas genómica de H.chilense e pTa71; e com as sondas SSR (AAC)5, 5S rDNA e pSC119.2 permitiram detectar os rearranjos e identificar os cromossomas neles envolvidos. Inicialmente, detetaram-se oito sinais de hibridação da sonda (AG)10 no tritordeum HT27, e seis sinais em trigo rijo devido à ausência de um sinal de hibridação (AG)10 no par cromossómico 1B de trigo. Este sinal resultou de uma sequência de rearranjos estruturais: uma dupla inversão pericêntrica no cromossoma 6B que resultou em duas regiões (AG)10 pericentroméricas (uma no braço curto e outra no braço longo). O cromossoma derivado, der(6B) recombinou-se com o cromossoma 1B resultando na translocação recíproca Robertsoniana que originou os dois pares de cromossomas 1BS.6BL e 6BS.1BL. Provavelmente estes rearranjos que envolveram as regiões SSR (AG)10 e (AAC)5 foram induzidos pela alopoliploidização e mediados pela actividade de RTNs. Comparando os resultados moleculares com os citogenéticos, verificou-se que: (1) - a maioria dos marcadores herdados pelo tritordeum tiveram origem no progenitor trigo; (2) - à excepção do sinal de hibridação adicional observado no cromossoma 1B de tritordeum, os sinais de hibridação (AG)10 em tritordeum também foram herdados de trigo rijo; (3) - os rearranjos estruturais ocorreram ao nível dos cromossomas nucleolares 1B e 6B do trigo. Considerando que os SCoTs são marcadores de regiões codificantes do genoma e que a maioria dos SCoTs em tritordeum foram herdados do trigo, estes resultados suportaram a hipótese da utilização deste anfiplóide como cereal alternativo para agricultura, e como material-ponte no âmbito de programas de melhoramento de trigo.
The allopolyploid nucleus experience irreversible genetic and epigenetic modifications. Triticeae tribe constitutes an excellent taxon for studying genomic restructuring in newly formed allopolyploids. The major goal of this study was to verify the potential occurrence of genetic restructuring at the molecular and cytogenetic levels in newly formed tritordeums (allopolyploids H.chilense x T.turgidum) by comparison with their parents. The amphiploidy of tritordeums was previously confirmed by FISH. DNA fingerprint of two newly formed lines of hexaploid tritordeum (HT22 and HT27) and respective parents using IRAP, REMAP, ISSR and SCoT markers was performed. Six combinations of LTR primers and seven combinations of one LTR and one SSR primer produced IRAPs and REMAPs, respectively. Among 60 primers SCoT tested, only 18 amplified SCoTs in line HT22 and 19 in line HT27. After the presence/absence analysis of bands among tritordeums and their parents, it was detected polymorphic bands: i) common to tritordeum and one of the parents, ii) exclusively amplified in tritordeum and/or iii) specific to one of the parents. Globally, all markers produced in tritordeum were mostly inherited from the wheat parent. The novel bands amplified in tritordeum (and those eliminated) were considered allopolyploidization-induced genetic rearrangements. Among the markers used, IRAPs, REMAPs and ISSRs, evidenced better the genetic restructuring in tritordeum. Cytogenetically, it was tested different SSR probes in mitotic chromosome spreads of newly formed tritordeums and their parents by ND-FISH. Only the SSR (AG)10 probe revealed structural rearrangements in the nucleolar chromosomes 1B and 6B of tritordeum. Successive FISH experiments with the probes: genomic of H.chilense and pTa71; and SSR (AAC)5, 5S rDNA and pSC119.2, simultaneously, allowed the detection of rearrangements and identification of the involved chromosomes. Firstly, it were detected eight hybridization signals of (AG)10 in tritordeum HT27, and six signals in durum wheat, due to the absence of an hybridization signal (AG)10 in the wheat chromosome pair 1B. The novel signal resulted from a sequence of structural rearrangements: an inverted pericentric duplication in the 6B chromosome which resulted on two (AG)10 pericentromeric regions (one in the short and other in the long arm). The derivative chromosome, der(6B) recombined with the 1B chromosome resulting on the reciprocal Robertsonian translocation that originated the two chromosome pairs 1BS.6BL and 6BS.1BL. Probably, these rearrangements which involved the SSR regions (AG)10 and (AAC)5 were induced by allopolyploidization and mediated by RTNs activity. Comparing the molecular with the cytogenetic results, it was verified that: (1) – most of the markers inherited by tritordeum had origin in wheat parent; (2) – except for the novel hybridization signal observed in the 1B chromosome of tritordeum, the hybridization signals (AG)10 in tritordeum were also inherited from durum wheat; (3) - the structural rearrangements occurred in the wheat nucleolar 1B and 6B chromosomes. Considering the SCoTs as markers of coding regions in the genome and that most of the SCoTs in tritordeum were inherited from wheat, these results supported the hypothesis of the use of this amphiploid as alternative cereal in agriculture, and as bridge-material under the scope of wheat breeding programs.

Includes bibliographies.
xiv, 175, [96] leaves, [17] leaves of plates : ill. (some col.) ; 30 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
This thesis reports on the generation of molecular tools for the analysis of chromosome 6R of rye and the application of these tools in structural analysis of 6RL. Results presented include physical and genetic maps of chromosome 6RL incorporating RFLP and PCR markers and CreR, the locus conferring resistance to cereal cyst nematode (CCN). The ability to detect small introgessions of rye chromatin in wheat is demonstrated.
Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 1997

Introduzione: Numerosi studi hanno accertato il ruolo dei markers molecolari e citogenetici, specialmente in pazienti con carcinoma renale a cellule chiare (ccRCC) , allo scopo di aumentare l’accuratezza diagnostica raggiungibile con le classiche caratteristiche clinico patologiche del tumore. Obiettivo: Il principale scopo del presente studio era quello di valutare il potenziale ruolo della perdita del cromosoma 9p e del 14q come predittori di rischio di recidiva in una coorte di pazienti andati incontro a nefrectomia parziale (PN) o radicale (RN) per carcinoma renale a cellule chiare (ccRCC) non metastatico. Materiali: Abbiamo identificato la perdita del cromosoma 9p e 14q in 175 pazienti che erano stati sottoposti a nefrectomia parziale o radicale tra il 1990 e il 2000 per carcinoma renale a cellule chiare non metastatico. Nessun paziente aveva ricevuto trattamento adiuvante dopo la chirurgia. Metodi: Abbiamo eseguito un’analisi citogenetica in interfase, (F.I.S.H:fluorescence in situ hybridization ) utilizzando una specifica sonda telomerica (115 kb) che mappa sui telomeri del cromosoma 9p e 14q (SpectrumGreen LSI, Abbott) e una sonda centromerica (alpha-satellite DNA) che mappa sul cromosoma 9p11-q11. Per ogni paziente abbiamo estratto dall’archivio tutte le piu’ rilevanti caratteristiche cliniche. Abbiamo identificato nella sopravvivenza libera da malattia (DFS: disease-free serviva) il nostro principale parametro di valutazione prognostico. Abbiamo generato differenti modelli di analisi statistica multivariata allo scopo di dimostrare il valore predittivo indipendente delle anomalie citogenetiche analizzate, quando aggiustate in base agli effetti dei principali parametri usati per stratificare i pazienti in categorie di rischio durante le prove di fase 3 di valutazione di efficacia di nuove terapie adiuvanti. Risultati e limiti: In 135 casi (77.1%) non abbiamo osservato alterazioni citogenetiche, in 14 casi (8%) e in 9 casi (5.1%) abbiamo osservato la perdita del cromosoma 9p o 14q rispettivamente. In 17 casi (9.7%) si è osservata la contemporanea presenza delle due alterazioni citogenetiche. La durata del follow-up medio era di 36 mesi (interquartile range: 21–78). La simultanea perdita del cromosoma 9p and 14q è risultato essere un fattore predittivo indipendente di DFS, una volta aggiustato in base agli effetti della dimensione tumorale (pT) e del grado di differenziazione (G) (hazard ratio [HR]: 4.579; 95% confidence interval [CI], 1.767 11.868), del Leibovich score (HR: 3.704; 95% CI, 1.565–8.768), o dell’ UCLA Integrated Staging System (UISS; HR: 3.194; 95% CI, 1.351–7.553). Il piu’ rilevante limite del nostro studio è il campione di analisi relativamente piccolo. Conclusioni: la perdita del cromosoma 9p e 14q è un parametro predittivo indipendente di sopravvivenza libera da malattia (DFS) in pazienti andati incontro a nefrectomia parziale (PN) o radicale (RN) per carcinoma renale a cellule chiare (ccRCC) non metastatico , una volta aggiustato in base ai parametri o del Leibovich score o del sistema UISS. Questo studio dimostra che la sopravvivenza libera da recidiva in pazienti candidabili a protocolli di terapia adiuvante potrebbe essere fortemente influenzata dalle caratteristiche citogenetiche del tumore.
Background: Several studies have assessed the role of molecular and cytogenetic markers, especially in patients with clear cell renal cell carcinoma (ccRCC), with the intent of increasing the prognostic accuracy that is achievable with the classic clinical and pathologic features. Objective: The main purpose of the present study was to evaluate the potential role of loss of chromosomes 9p and 14q as predictors of the risk of recurrence in a cohort of patients who underwent partial nephrectomy (PN) or radical nephrectomy (RN) for nonmetastatic ccRCC. Design, setting, and participants: We evaluated the loss of chromosomes 9p and 14q in 175 patients who underwent PN or RN between 1990 and 2000 for nonmetastatic ccRCC. None of the patients received adjuvant treatment after surgery. Intervention: We performed an interphase cytogenetic fluorescence in situ hybridization analysis using a telomeric-specific probe (115 kb) mapping on the chromosome 9p and 14q telomeres (SpectrumGreen LSI, Abbott) and a centromeric (alpha-satellite DNA) probe mapping on chromosome 9p11-q11. Measurements: For each patient, we extracted from the database all of the most relevant clinical records. Disease-free survival (DFS) was the main outcome of the study. We generated different multivariable models with the intent of demonstrating the independent predictive role of cytogenetic abnormalities once adjusted for the effects of the most common tools used to stratify patients in ongoing phase 3 trials evaluating the efficacy of adjuvant therapies Results and limitations: No cytogenetic abnormalities were observed in 135 cases (77.1%), and loss of chromosome 9p or 14q was detected in 14 cases (8%) and 9 cases (5.1%), respectively. The contemporary presence of both cytogenetic alterations was reported in 17 cases (9.7%). The median follow-up duration was 36 months (interquartile range: 21–78). The simultaneous loss of both chromosomes 9p and 14q turned out to be an independent predictor of DFS, once adjusted for the effects of pT and nuclear grade (hazard ratio [HR]: 4.579; 95% confidence interval [CI], 1.767 11.868), Leibovich score (HR: 3.704; 95% CI, 1.565–8.768), or UCLA Integrated Staging System (UISS; HR: 3.194; 95% CI, 1.351–7.553). The most relevant limitation is the relatively small sample of evaluated patients. Conclusions: Loss of chromosomes 9p and 14q was an independent predictor of DFS in patients who underwent PN or RN for nonmetastatic ccRCC, once adjusted for the effects of either Leibovich score or UISS. This study demonstrates that the recurrence-free survival of patients suitable for adjuvant protocols could be strongly influenced by the cytogenetic characteristics of the tumor.

Supernumerary marker chromosomes (sSMCs) are a relatively rare cytogenetic phenomenon. Their laboratory examination is often difficult, and the clinical interpretation is even more challenging. The main reason is that most sSMC carriers have no clinical manifestations. The chromosome origin and exact range of the aberration are very important, as well as the fact that sSMCs are often found in mosaics that can strongly influence both the phenotype and the interpretation of result. Prenatal sSMC finding is one of the most challenging situations in both clinical and laboratory genetics. This work deals with the investigation process of sSMC carriers using molecular cytogenetic techniques, especially fluorescence in situ hybridization (FISH). We investigated a total of 67 families collected both prospectively and retrospectively, and we found 70 unique sSMCs in a total of 74 individuals. Six cases were familial and in three cases two sSMCs were found in one individual. According to the initial karyotype finding, the cases were divided into two groups, sSMCs supernumerary to a normal karyotype (group A) and sSMCT s supernumerary to the Turner karyotype (group B). The chromosomal origin was successfully determined in 88,6 % sSMCs. In group A the most common findings were sSMCs derived from chromosome 15,...

The primary focus of this diploma thesis is on marker chromosomes and phenotypically similar human karyotype polymorphisms, variants of short acrocentric arms in particular. The first half provides a very useful review of literature concerning different aspects of both sSMC and human polymorphisms such as their origin, inheritance, associated phenotype, formation and molecular cytogenetic methods that are applied in the process of identification of these aberrations. The methodical emphasis is on FISH and its modifications (e.g. M-FISH, acro M FISH, cen M-FISH) as well as on the CGH methods. The main objective was to test the above-mentioned methods and state their limitations and applications. Thus, in the other half we provide evaluations of commonly used methods and introduce new strategies that could be implemented to make the identification of these additional chromosomes or satellite translocations more effective. All the conclusions are based on the analysis of 7 patients with sSMC and 4 patients with variants involving acrocentric NOR regions. The results of our thorough research into their karyotypes have been compared with similar findings in the literature. Last but not least, we tried to establish a link between observed abnormalities and the type of a chromosomal aberration at hand.

Tese de doutoramento em Medicina (Ciências Biomédicas), apresentada à Faculdade de Medicina da Universidade de Coimbra
Cromossomas marcadores supranumerários sSMCs, do inglês, small Supernumerary Marker Chromosomes) são pequenos cromossomas estruturalmente anormais que aparecem adicionalmente aos 46 cromossomas humanos e que não podem ser identificados ou caracterizados por citogenética convencional, tendo um tamanho inferior a um cromossoma 20 da mesma placa metafásica. Os sSMCs constituem um grupo heterógeneo de cromossomas anómalos que podem ter diferentes formas, como cromossomas duplicados invertidos (inv dup), cromossomas minute cêntricos (min) e cromossomas em anel (r). O risco de alterações fenotípicas associadas à presença de um sSMC depende de vários factores, como a hereditariedade, a origem do cromossoma, a morfologia, o conteúdo genético, a presença de dissomia uniparental ou o grau de mosaicismo. De facto, os fenótipos associados a um sSMC são variáveis, desde normais a severamente afectados. Os sSMCs podem ser detectados em diagnóstico pós-natal ou em pré-natal constituindo, sobretudo no último caso, um problema complexo para a investigação citogenética e o aconselhamento genético. Tendo em conta dados publicados na literatura que estimam uma frequência de 0.044% recém-nascidos portadores de um sSMC e que a população mundial é estimada actualmente em cerca de 6 823 000 000 pessoas, pode-se extrapolar o número de aproximadamente 3 milhões de indíviduos no mundo portadores de um sSMC. A grande maioria destes indíviduos não tem manifestações fenotípicas aparentes, no entanto cerca de 26% dos casos de indivíduos com um sSMC terão manifestações fenotípicas que poderão ser mais ou menos severas. A maioria dos cromossomas marcadores publicados na literatura não têm uma caracterização citogenética detalhada, quer da origem quer do conteúdo genético, que permita uma correlação robusta com o fenótipo esperado. Este facto dificulta o aconselhamento genético quando é encontrado um sSMC, sobretudo em diagnóstico pré-natal. Neste domínio é essencial sistematizar o conhecimento sobre o conteúdo genético envolvido nos sSMC e a descriminação das manifestações fenotípicas expectáveis de um indivíduo ou grupo de indivíduos, sejam elas normais ou anormais. Com este trabalho pretendeu-se contribuir para esta sistematização, procedendo-se à caracterização por citogenética molecular de um grupo de cromossomas marcadores supranumerários derivados de vários cromossomas, nomeadamente dos cromossomas 1, 2, 5, 11, 13, 15, 16, 17, 18 e 22. Pretendeu-se validar a técnica de hibridização Genómica Comparativa por array (array CGH, do inglês array Comparative Genomic Hybrydization) para caracterização da extensão genética do cromossoma marcador, após a sua microdissecção e amplificação. Concluiu-se que esta técnica será de grande utilidade para a correcta caracterização de sSMCs sobretudo quando o cromossoma marcador está presente em mosaico de baixa expressão. Após caracterização molecular do grupo de sSMC em estudo estabeleceu-se, na medida do possível, uma relação genótipo/fenótipo, comparando cada caso com outros casos reportados na literatura. Neste trabalho propõem-se ainda linhas de orientação para lidar com casos de sSMC num laboratório de diagnóstico em citogenética, tendo em consideração factores como por exemplo o tempo para a caracterização citogenética, o grau de mosaicismo e as técnicas disponíveis no laboratório. O trabalho incluído nesta dissertação reforça e clarifica a necessidade de uma caracterização citogenética molecular detalhada de cromossomas marcadores supranumerários, recorrendo nomeadamente a técnicas de M-FISH e de array CGH. Esta caracterização possibilita o estabelecimento de relações genótipo/fenótipo cada vez mais precisas e essenciais para um correcto aconselhamento genético, por parte do Geneticista Clínico.
Small supernumerary marker chromosomes (sSMCs) are small structurally abnormal chromosomes that occur in addition to the 46 human chromosomes, that cannot be identified or characterized unambiguously by conventional banding cytogenetics alone, and are (in general) equal in size or smaller than a chromosome 20 of the same metaphase spread. sSMCs are a morphologically heterogeneous group of structural abnormal chromosomes that can appear in different shapes: inverted duplicated chromosomes (inv dup), centric minute chromosomes (min) and ring chromosomes (r). The risk for phenotypic abnormalities associated with a sSMC depends on several factors, including nheritance, chromosomal origin, morphology, genetic content, presence of uniparental disomy or grade of mosaicism. In fact, phenotypes associated with a sSMC are variable, from normal to severely affected. sSMCs can be detected postnatally or prenatally, the last being a major problem for cytogenetic investigation and genetic counselling. Taking into account data in the literature that estimate a 0.044% frequency of newborns with a sSMC and that the estimated world population is 6 823 000 000 people, there will be at present approximately 3 million living sSMC carriers. The great majority of these carriers will not have apparent phenotypical consequences. However, about 26% of individuals with a sSMC will have phenotypical manifestations, more or less severe. The majority of sSMCs published in the literature do not have an accurate cytogenetics characterization, of the origin and genetic content of the marker, which allows a robust correlation with the expected phenotype. This is a difficulty for genetic counselling when a sSMC is encountered, especially at prenatal diagnosis. It is essential to systematize the knowledge of the genetic content of markers and the phenotypical manifestations encountered, normal or abnormal. With this work we want to contribute to this systematization, by doing a detailed molecular cytogenetic characterization of a group of sSMC derived from different chromosomes, namely chromosomes 1, 2, 5, 11, 13, 15, 16, 17, 18 and 22. We aimed to validate array CGH technique, after the microdissection and amplification of the marker, for the characterization of the genetic extension of the sSMC. We concluded that this technique is of great value for an accurate characterization of the marker, especially when the sSMC is present in low levels of mosaicism. After the characterization of the group of sSMCs cases in study, it was established a genotype/phenotype correlation, whenever possible, and a comparison of each case with those described in the literature was done. In this work, guidelines are proposed for the management of sSMCs in a diagnostic cytogenetic laboratory, taking into account several factors, like time available for the cytogenetic characterization, levels of mosaicism and techniques availability in the lab. This work reinforces and clarifies the need of an accurate molecular cytogenetic characterization of sSMCs, using particularly M- FISH techniques or array CGH. This characterization allows the establishment of more precise enotype/phenotype correlations, which are essential for an accurate genetic counselling by the Clinic Geneticist.

博士
國立臺灣大學
臨床醫學研究所
102
Introduction Chronic lymphocytic leukemia (CLL) is an indolent clonal lymphoid neoplasm. In Western countries, CLL is the most common leukemia in adults. However, CLL is much less prevalent in Eastern countries, including Taiwan. At present, data on CLL, including the clinical picture, epidemiology, and molecular studies, are mainly derived from western countries. Few studies have addressed the similarities and differences of CLL between Western and Eastern countries. Patients and Methods Epidemiologic data for CLL in Taiwan, including the incidence rate and survival, were obtained from the Taiwan National Cancer Registry. The corresponding data for Caucasian Americans were obtained from the Surveillance, Epidemiology, and End Results database. The age-specific incidence rates of CLL for both populations were plotted by calendar year at diagnosis and by birth cohort. The individual effects of time period and birth cohort on the trends of the CLL incidence in both populations were analyzed using an age-period-cohort model. The relative survival (RS) of CLL patients in both populations was estimated as the observed survival among the cancer patients adjusted by the expected survival for a comparable group from the general population. Cytogenetic abnormalities (CA) were analyzed in a cohort of Taiwanese CLL patients (n=83) by both conventional cytogenetics (CG) and fluorescence in situ hybridization (FISH) and compared with data from Western countries. Furthermore, stem-cell factor (SCF) expression, a hypothesized prognostic marker, was also explored using immunohistochemical staining in bone marrow biopsy samples from CLL patients. Results The age-adjusted incidence rate of CLL for Taiwanese continuously increased during a 20-year period while that for Caucasian Americans remained steady. A much stronger birth-cohort effect was identified in Taiwanese compared with Caucasian Americans. This effect corresponded to the westernization of the lifestyle in Taiwan since 1960. Overall, despite its indolent course, CLL drastically shortened patients’ life expectancy in both Taiwan and the US, and the decrease in RS in Taiwan was much larger than that in the US. Intriguingly, RS in Taiwan improved in patients diagnosed after 1995, a time period corresponding to the introduction of Taiwan National Health Insurance. This improvement was observed mainly in patients younger than 65 years while RS in older patients remained unchanged. After adjustment for age and gender effects, the diagnosis period remained an independent factor contributing to changes in RS in Taiwanese patients. CA were seen in 35 patients (42.2%) by CG analysis and 58 (69.9%) patients by FISH analysis Both CG and FISH showed that deletion of 17p or 11q was associated with poorer overall survival (OS), whereas isolated 13q deletion was associated with better OS. Trisomy 3 was found in five patients by CG, all of whom were in Binet stage A but had very poor OS; this prognostic impact was independent of other CA and Binet stages. Strong SCF expression in CLL cells in a small cohort seemed to predict poor OS, especially in patients with Binet B/C disease. Conclusions In addition to the ethnic differences in the incidence, there was a distinct increased incidence trend of CLL in Taiwan. The strong birth-cohort effect underlying this trend suggests that lifestyle and environmental factors play a role in the development of CLL in Taiwanese. The survival of Taiwanese CLL patients was generally poor and inferior to that of US patients. However, the outcomes in younger patients have improved since 1995, possibly resulting from the availability of better medical care, suggesting that treatment advances have improved the outcome of CLL. Nevertheless, the survival of older patients remains poor and is in need of improvement. Although the disease incidences are different, the CA in Taiwanese patients with CLL are similar to those in the West; combined CG and FISH analysis is also able to predict outcomes in Taiwanese patients. The clinical significance of trisomy 3 as a poor prognostic factor warrants further validation. Finally, SCF expression might be a novel prognostic marker that warrants further verification with a larger cohort.

The focus of this diploma thesis is on mosaic numerical and structural chromosomal aberrations. In its theoretical part, general problems of mosaicism, its phenotypic effect, mechanisms of origin, related epigenetic modifications, and diagnostic options are described. The methodical part of the thesis then primarily refers to fluorescence in situ hybridization (FISH) and its application in the diagnostics of mosaicism. This method was used in the examination of 29 patients with numerical as well as structural abnormalities of autosomes or gonosomes with proven or suspected mosaicism. On the basis of this analysis, possible errors of measurement were determined and data for statistic evaluation were retrieved. For the examinations of three patients an alternative of the comparative genomic hybridization, the array CGH technique, was applied. The FISH method, although being based on random selection and human factor, proved sufficient sensitivity as well as specificity in the field of low-frequency mosaicism diagnostics. The main critical factors responsible for potential misinterpretation of the data arose from inherent characteristics of the biological material, incorrect targeting of the analysis, probe instability, bleed through effect and absence of mitosis during the structural aberrations analysis.

The aim of this study was to analyse testcross-material that was generated during a homoeologous pairing-induction experiment. Absence of the homoeologous pairing suppressor gene, Ph1, was employed to induce meiotic pairing between the Lr59 translocation (Aegilops peregrina) and 1AL of normal wheat. The study aimed to characterize the test-cross plants derived from this experiment and to identify recombinants which retained the least amount of species chromatin but which still contained the Lr59 gene. The test-cross F1 population, 07M5 (total 635 plants), was screened for Lr59 resistance by inoculating seedlings with the leaf rust pathotype, UVPrt8. The 168 resistant plants were characterized with molecular markers in order to identify recombinants. The data were used to construct a physical map which showed the relative sizes of the recombinants and which could be used to identify those recombinants which contained the least amount of residual species chromatin. Microsatellite (Xcfa2219, Xbarc83 and Xgwm164) and SCAR (S15T3) analysis was used for the initial identification of recombinants. The results showed that 152 of the 168 resistant plants were recombinants for the four loci; that eight of the remaining 16 plants represented non-recombinant, wild species-types and that the last eight plants represented the wheat parental-types which were resistant (and thus, also recombinants). This extremely high recombination frequency can largely be attributed to strong segregation distortion that was evident in the cross. It is also possible that the translocation segment could derive from the S genome rather than the U genome of Ae. peregrina. The S genome is closer related to the wheat genomes than the U genome and may be more prone to recombination. With the use of the microsatellite and SCAR data, a physical map was constructed which showed the relative location of the Lr59 gene on the translocation. It appeared that the eight shortest recombinants retained terminal species chromatin. In an attempt to characterize the eight recombinants, additional marker loci had to be identified within that region. RAPD, iv AFLP and DArT markers were investigated for this purpose. RAPD analyses did not produce any useful markers. AFLP and DArT analyses did identify useful markers with which the eight recombinants could be screened. The data showed which recombinants probably retained the least amount of species chromatin. Seeing that AFLP and DArT markers are anonymous and that the distances between marker loci are unknown, it is not possible to say which recombinant is the shortest and consequently it will be nessecary to also evaluate the group of eight recombinants agronomically in order to identify the most useful ones. The results showed that multiple cross-overs apparently occured on both sides of Lr59. Multiple cross-overs are higly unlikely in material of this nature, therefore it was speculated that the observation resulted from incomplete synteny between the telomeric areas of the translocation and 1AL. A structural difference between the two chromosome regions might have given rise to abnormal meiotic pairing structures and thus unexpected gamete genotypes. Each of the eight recombinants did express one or more of the Ae. peregrina derived AFLP loci which can in future be verified for use as a marker for marker assisted selection. The study succeeded in identifying a number of potentially useful recombinants which contain the Lr59 resistance. It would, however, be risky to select only one of the shortest recombinants for further development on the basis of the present knowledge as some recombinants may contain genetic abnormalities which resulted from reduced synteny in the Lr59 region. It would therefore be wise to further evaluate all eight recombinants before the best one is selected for agronomic use.

MSCAGR (Animal Science)
Department of Animal Science
The Nguni is a transboundary indigenous Southern African cattle breed. The breed has distinct populations that are adapted to the different ecological zones of Southern Africa. Previous work on characterising the Nguni has been limited to within-country studies. Thus, the aim of the current study was to genetically characterise South African (SA) Nguni, Mozambican Nguni (Landim) and Swazi Nguni populations across Southern African region using a panel of 25 microsatellite markers, recommended by FAO and ISAG for genetic diversity studies. Genotypic data were generated from 90 unrelated autosomal DNA samples of the three cattle populations (SA Nguni n=30, Mozambican Nguni (Landim) n=30 and Swazi Nguni n=30) collected from government research stations and stud herds. Five South African beef cattle breeds’ DNA profiles were obtained from the ARC-DNA database and used as reference populations. A majority of the microsatellite markers were highly polymorphic across the studied populations. High genetic diversity was detected and expected heterozygosity varied from 71% (Landim) to 75% (SA Nguni) with a higher mean number of alleles (MNA) in the SA Nguni (7.52±0.42) compared to the Swazi Nguni (6.92±0.40) and Landim (7.16±0.43) populations. Observed heterozygosity (Ho) (0.597±0.046) compared to expected heterozygosity (He) (0.719±0.022) was lowest for the Swazi Nguni, confirming a relatively high level of inbreeding (FIS=0.158) in that population. An analysis of molecular variance (AMOVA) revealed that 9.61% of the total variation occurred among populations, while 90.39% occurred within populations. Short genetic distance (29.9%) was observed between Landim and Swazi Nguni, with the SA Nguni (>50%) being the most genetically distant population. The distant relationship between SA Nguni and the other two Nguni cattle populations was further confirmed by neighbor-joining (NJ) tree, Principal Coordinates Analyses (PCoA) and Factorial Corresponding Analysis (FCA). The structure of the three Nguni cattle populations clustered independently, despite some evidence of admixture. Additionally, genetic differentiation and population structure within four Mozambican indigenous cattle populations were investigated using the same panel of microsatellite markers. The analysis of unrelated autosomal DNA was performed on 120 animals (Angone n=30, Bovine de Tete n=30, Landim n=30 and Namaacha Nguni n=30), which presented sufficient genetic diversity across all populations. Estimates of mean number of alleles, observed and expected heterozygosities were 6.920±0.20, 0.68±0.02 and 0.71±0.01, respectively. Genetic differentiation among the populations accounted for 8.02% of total genetic variability. Negative (-0.025±0.029) to low positive (0.073±0.050) levels of inbreeding were observed within the four populations. The genetic distance, NJ tree, PCoA and FCA revealed a close relationship between Bovine de Tete and Landim as opposed to Angone and Namaacha Nguni. STRUCTURE analysis assigned the four Mozambican populations independently; however Bovine de Tete and Landim showed relatively higher levels of admixture with each other than Angone and Namaacha Nguni. It can be concluded that SA Nguni, Landim and Swazi Nguni populations accomplish high genetic diversity and they are genetically distant; however, the two latter populations are closely related. These results present useful information
NRF