Allele Diversity of the DRB1 Gene of the Major Histocompatibility Complex in Two Species of Hamsters of the Genus Allocricetulus Argyropulo 1932

For the first time, the allelic diversity of exon 2 of the DRB1 gene (class II of the major histocompatibility complex, MHC) was determined by NGS sequencing in natural populations of two species of hamsters of the genus Allocricetulus: Eversmann’s hamster (A. eversmanni) and the Mongolian hamster (A. curtatus). These species are genetically close, but allopatric and demonstrate different habitat preferences. Eversmann’s hamster inhabits the steppes and is often associated with anthropogenic landscapes, while the Mongolian hamster prefers semi-deserts and deserts, where anthropogenic pressure is almost absent. The analysis revealed a significant effect of positive selection on the diversity of alleles of the DRB1 gene in both species studied. However, Eversmann’s hamster is characterized by a large average distance between alleles, but a smaller proportion of heterozygous individuals, while the Mongolian hamster is characterized by a large individual variety of alleles. Thus, despite the extensive range of Eversmann’s hamster, we noted significantly less genetic diversity of adaptive genes, which may be due to increased anthropogenic exposure.