title: Heterochromatin variation and sex chromosome polymorphism in Nesokia indica: a population study.
abstract: Nesokia indica, the Indian mole rat, exhibits extensive variability (polymorphism) for the constitutive heterochromatin of the X and Y chromosomes. These polymorphic X and Y types range from a large metacentric chromosome to a small acrocentric one and occur in different frequencies in the population. On the assumption that there is random mating among individuals carrying these various X and Y chromosomes, the population shows Hardy-Weinberg proportions for the genotypes. However, notwithstanding the partial or total loss of constitutive heterochromatin of the X and Y chromosomes in a few individuals, its retention in most of the animals seems obligatory to the population at large. Hence, we suggest that the C-heterochromatin plays a "regulatory" role in the population dynamics of this species.
mesh_terms: D000818:Animals; D005260:Female; D005787:Gene Frequency; D014644:Genetic Variation; D005828:Genetics, Population; D005838:Genotype; D006570:Heterochromatin / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D009115:Muridae / Q000235:genetics*; D011110:Polymorphism, Genetic; D012730:Sex Chromosomes / Q000648:ultrastructure*
chemical_list: D006570:Heterochromatin