Heterogeneity of the Southeast Belarusian mitochondrial gene pool.

The study of mitochondrial DNA (mtDNA) variability at the level of whole mitogenomes has significant implications for the fields of human evolution and population genetics. In this paper, we present the results of a study of the complete mtDNA variability in Belarusians from the southeastern part of the Republic of Belarus. It was found that Southeast Belarusians are characterized by a high diversity of mitochondrial genomes. The analysis of genetic distances between European populations showed significant differences between the studied Belarusian sample from the bulk of East European populations, including Slavic ethnic groups. The results of the phylogeographic analysis indicated the presence of the West Asian component (12.6%) in the Belarusian mitochondrial gene pool, which can account for the observed genetic differences between Belarusians and other Eastern Slavs (Russians and Ukrainians). The East Asian component of the mitochondrial gene pool of the studied group of Belarusians is represented by haplogroup C5c1a (2.3%). The results of the phylogeographic analysis indicated that this mtDNA subclade is predominantly present in the gene pools of Slavic peoples, including Poles, Belarusians, Ukrainians, and Russians. The evolutionary age of haplogroup C5c1a is ~4000 years and, consequently, the appearance of C5c1-haplotypes in the eastern regions of Europe may be linked to the migrations of the Caspian steppe populations to the west during the Bronze Age.