Polymorphism of two single nucleotide loci rs758130 (T/C) and rs2238296 (T/C) of mitochondrial DNA-polymerase gamma (POLG1) gene has been studied in individuals of different ethnoracial ancestry in Russians and Buryats) with already known genotypes of microsatellite CAG-repeat of this gene. It was found that alleles with the number of repeats unequal to 10 are more often detected on the background of haplotype TT than CC. Results of phylogenetic analysis of the POLG1 gene intron 2 nucleotide sequences in humans and chimpanzee have shown that haplotype TT heterogeneous in relation to CAG-repeat polymorphism appears to be evolutionary younger than haplotype CC. The data obtained can be used for further studies of relationships between CAG-repeat polymorphisms and male infertility.