When two alleles carried by a heterozygote are transmitted unequally to the zygote at the time of fertilization, transmission ratio distortion occurs. The best studied example of this phenomenon in mammals is t-haplotype in mice. The mouse t-haplotype is a selfish variant region on chromosome 17, in nature transmitted as a unit. Male mice homozygous for t haplotype are sterile, but heterozygotes transmit the t haplotype up to 99% of their progeny. This is believed to be caused by motility differences between sperm carrying the t haplotype and wild-type sperm from the same heterozygous male. The concrete mechanism of the postulated sperm competition in favour of t haplotype carrying sperm was so far not fully illuminated. During this project, we worked with the hypothesis that the differences in sperm motility putatively responsible for transmission ratio distortion are triggered, at least in part, by metabolic causes. Our results from ATP and mitochondrial membrane potential (MMP) comparison indeed suggest that there are metabolic dissimilarities in sperm from the different genotypes of t (t/t, t/+, +/+). Specifically, our data show that there is significantly less ATP in t/t sperm when compared to the other two genotypes. Likewise, sperm from t/t mice also seem to have lower MMP, suggesting that...

PREIMPLANTATION GENETIC HAPLOTYPING IN GENETICALLY RISK FAMILIES Abstract of Irena Borgulova's PhD study Page 1/1 ABSTRACT Preimplantation genetic diagnosis (PGD) is at the intersection of assisted reproduction and clinical genetics. PGD precedes prenatal diagnosis because consists in biopsy of a single embryonic cell and its examination excluding genetic risks before embryo transfer back to mother uterus. Methods within PGD can offer all spectrums of possible investigations of a single cell, whether focused on monogenic disorders, chromosomal aberration or abnormality of whole genome. Monogenic diseases in embryos can be detected by direct or indirect linkage analysis. Indirect linkage analysis has the advantage compared to direct analysis that it is able to indentify pertinent aberration of examined chromosome. Indirect linkage analysis is characterised by preimplantation genetic haplotyping (PGH) which is prime and important constituent of PGD cycle. PGH is based on family anamnesis for determination of pathologic/ high-risk (mutation-associated) haplotype and healthy/ low-risk (without mutation) haplotype by comparison with the haplotypes of other family members. PGD cycle requires in vitro fertilisation (IVF). IVF cycle includes hormonal stimulation, biopsy of oocytes and their fertilisation outside...

Greater sage-grouse (Centrocercus urophasianus) currently inhabit about 56% of pre-settlement distribution of potential habitat. In 2005, the Castle Country Adaptive Resources Management Local Working Group (CaCoARM) was formed to address concerns regarding local sage-grouse populations in Carbon and Emery counties. In 2006-2007, CaCoARM identified the Wildcat Knolls and Horn Mountain as areas of special concern for greater sage-grouse conservation. Both sites selected by the group were inhabited by what appeared to be small isolated sage-grouse populations. Factors limiting small isolated greater sage-grouse populations throughout its range are diverse and largely site-specific. During 2008-2009, I captured, radio-collared, and monitored 43 sage-grouse between the two populations to document their ecology and seasonal habitat use patterns. The sites are only 24 km apart, but the populations appear to be isolated from each other. Sage-grouse on Horn Mountain and Wildcat Knolls are one-stage migratory and non-migratory, respectively. Although nesting and brooding success varied between sites, my results were comparable to those published in studies throughout the species' range. Overall male survival was lower on the Wildcat Knolls than Horn Mountain (P = 0.003). Hens that selected brood sites exhibiting increased shrub cover and grass height were more successful than hens that selected sites with lower shrub cover and lower grass height. Potential nesting habitat on the Wildcat Knolls and Horn Mountain were estimated at 2,329 and 5,493 ha, respectively. Hens that selected nest sites farther from non-habitat edge were more successful than hens that selected nest sites that were closer to non-habitat edge on the Wildcat Knolls. Higher nest success observed on the Wildcat Knolls was attributed to less habitat fragmentation. Isolated populations of greater sage-grouse are more susceptible to lower amounts of genetic diversity that may lead to inbreeding depression and increased rates of disease and parasites. I collected mitochondrial DNA samples from both the Wildcat Knolls and Horn Mountain populations. Although the haplotype frequencies recorded in the Wildcat Knolls and Horn Mountain populations were low, one was shared with several Utah populations. The documented low genetic diversity (especially on Horn Mountain) confirmed the isolation suspected by the local working group. Microsatellite tests may provide insights to enhance understanding of genetic differences among sites, and assist managers in determining whether or not translocations are necessary to maintain population genetic diversity. Biologists should not only continue to take samples for genetic comparison, but also record morphometric and behavior data.

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The mitochondrion is a tiny organelle that is the power supplier of the cell and vital to the functioning of the body organs. Additionally it contains a small circular genome of about 16 kb, present in many copies which makes the mitochondrial DNA more viable than nuclear DNA. Mitochondrial DNA is also maternally inherited and thus provides a direct link to maternal relatives. These two properties are of particular use for forensic samples, which only contain limited or degraded amounts of DNA, and for historical samples (ancient DNA). This thesis presents work on the mitochondrial DNA in the hypervariable regions (HV) I and II, in both contemporary and historical samples. Forensic genetics makes use of mitochondrial DNA analysis in court as circumstantial evidence, and population databases are used for the calculation of evidence value. Population samples (299) across Sweden have been analysed in order to enrich the EDNAP mtDNA database (EMPOP) (paper I). The application of mitochondrial DNA analysis allowed for analysis of historical skeletal remains: Copernicus, 1473-1543 (paper II), Karin Göring, 1888-1931 (paper III) and Medieval bones, 880-1000 AD, from a mass grave found in Sigtuna, Sweden (paper IV). The thesis also includes analyses of bones and teeth from the shipwrecked crew of the Vasa warship, 1628, samples from the Vasa museum, Stockholm, Sweden (paper V). Overall, the varying age of the samples and the different conservation environments (soil and water) accounted for variations in quality, but still allowed for successful DNA analysis.

Mutações no gene HFE têm sido apontadas como um dos principais fatores para o desenvolvimento de sobrecarga de ferro, especialmente os SNPs (single nucleotide polymorphism) clássicos C282Y e H63D. A sobrecarga de ferro pode ser primária, atribuída diretamente a mutações do gene HFE (hemocromatose hereditária - HH) ou adquirida em decorrência de fatores genéticos e de comorbidades, particularmente, infecção pelo vírus da hepatite C (HCV) e carcinoma hepatocelular (CHC). Desequilíbrio de ligação entre os SNPs principais do gene HFE com alelos dos genes HLA-A e HLA-B podem contribuir com alterações da função das células do sistema imunológico. Neste trabalho, sequenciamos a região codificadora do gene HFE (éxon 2, 3, 4 e 5) de pacientes que apresentam ou não sobrecarga de ferro primária ou adquirida. Assim, estudamos 130 pacientes com hepatite C, 60 pacientes com CHC, 14 pacientes com HH e 100 indivíduos saudáveis. Foram encontrados sete SNPs no gene HFE no sentido 5\' para 3\': i) H63D C>G no éxon 2 (rs1799945); ii) IVS2(+4)T>C no íntron 2 (rs2071303); iii) íntron 3 C>G (rs807209); iv) C282Y G>A no éxon 4 (rs1800562); v) íntron 4 G>A (rs2794717); vi) IVS4(-44) T>C (rs1800708); vii) no íntron 5 a deleção G>del, ainda não foi descrita na literatura. Foram realizadas as reconstruções de haplótipos da região codificadora e os haplótipos estendidos englobando o gene HFE e dez outros loci (HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQB1, TNFa, TNFb, TNFc, TNFd e HLA-G-14pb). Também, normatizamos a nomenclatura do gene de acordo com as regras do The International ImMunoGeneTics Information System - IMGT (http://www.imgt.org/). Diversas ferramentas foram utilizadas para avaliar a associação entre os sítios polimórficos do gene HFE com a sobrecarga de ferro, incluindo testes de associações avaliando alelos, genótipos, desequilíbrio de ligação, haplótipos e diplótipos, testes de diversidades e neutralidade. Finalmente, comparamos os SNPs do gene HFE encontrados na população saudável do presente trabalho com as diversas populações mundiais, disponíveis no sítio 1000genomes (http://www.1000genomes.org/). Os resultados demonstraram que a nossa a população estava mais próxima das populações europeias e americanas, sendo parcialmente próxima das populações africanas e distante das populações asiáticas. O alelo C282Y G, contido no haplótipo da região codificadora HFE*01:03, conferiu susceptibilidade a HH na população brasileira testada, concordando com os achados observados em outras populações mundiais. O diplótipo HFE*01:02:01:01/HFE*01:01:01:05 conferiu susceptibilidade para o desenvolvimento de sobrecarga de ferro em pacientes com CHC causado pelo HCV. Detectamos forte desequilíbrio entre os alelos H63D G e IVS2(+4) C no éxon 2 do gene HFE, e concomitantemente, desequilíbrio desses alelos com alelo HLA-B*44, aparentemente, sem associação com sobrecarga de ferro, mas com aparente origem histórica. Finalmente, o teste de diversidade encontrou diferenças apenas na amostra de HH e o teste de neutralidade não encontrou pressões seletivas na população controle do presente trabalho. Concluindo, este é o primeiro trabalho, avaliando grande segmento da região codificadora do gene HFE em diversas amostras de pacientes apresentando ou não sobrecarga de ferro e em indivíduos controle. / Mutations at the HFE gene have been identified as a major factor for the development of iron overload, especially the classical single nucleotide polymorphism (SNP) C282Y and H63D. Primary iron overload can be directly attributed to mutations in the HFE gene (hereditary hemochromatosis - HH), whereas secondary overload may be acquired due to genetic factors and comorbidities, particularly infection with hepatitis C virus (HCV) and hepatocellular carcinoma (HCC). Linkage disequilibrium between major SNPs at the HFE gene with HLA-A and HLA-B alleles may contribute to alterations in the function of immune cells. We sequenced the coding region of the HFE gene (exon 2, 3, 4 and 5) of patients exhibiting primary or secondary iron overload. Thus, we studied 130 patients with hepatitis C, 60 patients with HCC, 14 patients with HH and 100 healthy individuals. We observed seven SNPs in the HFE gene in 5 \'to 3\' sequence: i) H63D C>G at exon 2 (rs1799945); ii) IVS2(+4)T>C at intron 2 (rs2071303); iii) intron 3 C>G (rs807209); iv) C282Y G>A at exon 4 (rs1800562); v) intron 4 G>A (rs2794717); vi) IVS4(-44) T>C (rs1800708); vii) at intron 5 we detected a yet undescribed G>deletion. We performed haplotype reconstruction of the coding region and extended haplotypes comprising the HFE gene and ten other loci (HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQB1, TNFa, TNFb, TNFc, TNFd and HLA-G14bp). In addition, we normatized the nomenclature of the HFE gene, according to the rules of the International ImMunoGeneTics Information System - IMGT (http://www.imgt.org/). Several tools were used to evaluate the association between HFE polymorphic sites with iron overload, including tests assessing associations of alleles, genotypes, linkage disequilibrium, haplotype and diplotypes, diversity and neutrality tests. Finally, we compare the SNPs at the HFE gene observed in the healthy population with those observed in diverse worldwide populations available at the 1000genomes site (http://www.1000genomes.org/) the results showed that our population was closer to American and European populations, partially close the populations of African and distant of Asian populations. The C282Y allele G, contained in the coding region HFE * 01:03 haplotype, conferred susceptibility to HH in the Brazilian population tested, agreeing with the findings observed in other worldwide populations. The HFE*01:02:01:01/HFE* 01:01:01:05 dyplotype conferred susceptibility to the development of iron overload in patients with HCC caused by HCV. A strong linkage disequilibrium was detected between the H63D G and IVS2 (+4) C alleles in exon 2 of the HFE gene, and concomitantly, a linkage between these alleles with HLA-B*44, apparently not associated with iron overload, but with apparent historical origin. Finally, the test of diversity revealed differences only in the HH sample and the neutrality test detected no selective pressures on the control population of this study. In conclusion, this is the first study evaluating a large segment of the coding region of the HFE gene in several samples of patients exhibiting or not iron overload and in control subjects.

<p>Sexual assault is a significant problem facing the South African society. In this context, efficient but also affordable genotyping systems are needed for positive identification of criminals in incidences of sexual violence. The aim of this study was therefore to develop non-commercial Y-STR genotyping systems suitable for sexual assault cases in South Africa. Y-chromosome STR loci constituting the minimal haplotype are still the most widely used loci in investigating sexual assault cases despite the fact that DYS391 and DYS392 have shown low levels of polymorphism in Xhosa populations in Cape Town. The minimal haplotype was, therefore, further investigated in the Cape Muslim population. The Cape Muslim population generally exhibited high GD values among all the South African populations. These values were higher than 0.5 for most loci, and ranged from 0.447 for DYS391 to 0.957 for DYS385. The highest number of alleles in most loci was also recorded in this population. The overall assessment of the minimal haplotype has shown that this system is still a useful in investigating sexual assault case in many South African subpopulations. Therefore the exercise of internal validation of the minimal haplotype system was successfully carried out in the laboratory. iii The properties of additional novel and widely used STRs were also investigated in this study. Loci were successfully sequenced and allele nomenclature was assigned to them according to the ISFG guidelines.</p>

The aim of the present study was to evaluate the power of discrimination and genetic (diversity) parameters in the Y chromosome extended haploytpe markers in populations of Tanzania for forensic and populations studies. Eleven Y chromosome extended haplotype markers were selected for this study, these includes Minimal haplotypes markers i.e. DYS19, DYS390, DYS391, DYS392, DYS393, DYS385a/b, DYS389I/II and two additional markers DYS438 and DYS439. Six populations of Tanzania were investigated under this study. These populations were selected based on the language family categories / Niger Congo (Kuria and Sukuma), Nilo Saharan (Luo and Maasai) and Afro Asiatic (Iraqw and Alagwa).