Heterozygote disadvantage is potentially a potent driver of population genetic divergence. Also referred to as underdominance, this phenomena describes a situation where a genetic heterozygote has a lower overall fitness than either homozygote. Attention so far has mostly been given to underdominance within a single population and the maintenance of genetic differences between two populations e...

Recent studies have provided evidence that common genetic variations could account for a proportion of leukemia in adult or children. To evaluate the contribution of candidate gene association studies to the understanding of genetic susceptibility to acute lymphoblastic leukemia we conducted a systematic review from published studies. The polymorphisms of genes encoding carcinogen-metabolizi...

Twelve microsatellite loci of Leishmania braziliensis were examined, nine of which were developed in this work. Fifty-six Leishmania braziliensis were genotyped with these microsatellite loci. The 12 loci studied were polymorphic with the number of alleles ranging from five to 19, with a mean of 9.7 ± 4.1 and the observed heterozygosity averaging 0.425 ± 0.202. The important heterozygote defici...

The set of possible postselection genotype frequencies in an infinite, randomly mating population is found. Geometric mean heterozygote frequency divided by geometric mean homozygote frequency equals two times the geometric mean heterozygote fitness divided by geometric mean homozygote fitness. The ratio of genotype frequencies provides a measure of genetic variation that is independent of alle...

background: different studies show that chromosomal balance translocation in the parents can cause recurrent spontaneous abortions. incidence of chromosomal translocation abnormalities in couples with repeated abortions is from 0% to 31%. objective: the purpose of this research was studying the presence or absence of chromosomal abnormalities and heteromorphism in couples with recurrent abortio...

ATA presented in the preceding article (BRINK and BLACKWOOD 1961) D demonstrate that the effect of R' on aleurone color in maize is enhanced when the factor is carried by, or passed through, either of two reciprocal translocations, T2-10a and T4-lob, involving breaks in the long arm of chromosome 10 proximal to, but well removed from, the R locus. The change in phenotype is from darkly mottled ...

The order Scorpiones is one of the most cytogenetically interesting groups within Arachnida by virtue of the combination of chromosome singularities found in the 59 species analyzed so far. In this work, mitotic and meiotic chromosomes of 2 species of the family Bothriuridae were detailed. This family occupies a basal position within the superfamily Scorpionoidea. Furthermore, review of the cyt...

H E problem of position effect has been studied with the purpose of T elaborating upon the larger problem of gene action. DUBININ and SIDOROPP (1934) first showed the position effect of the fourth chromosome locus, cubitus interruptus, ( c i ) , in Drosophila melanogaster. They found that in translocations involving the fourth chromosome, the normal allele both in hemior homozygous constitution...

Adjacent-1 duplication-deficiencies (dp-dfs) are readily recovered from most heterozygous translocations in Gossypium hirsutum L., but frequencies of specific cytotypes differ widely in progenies from heterozygote (female symbol) x standard crosses. Surprisingly, these frequencies seem to be unrelated to the primary (postmeiotic) frequencies predicted by metaphase I configurations or to the pro...