Distribution of HLA antigens and haplotypes in the Buryat population of Siberia.

Polymorphisms of HLA-A, B, C, DR, and DQ antigens were investigated in a Mongoloid population named Buryat living in Siberia. HLA gene and haplotype frequencies were calculated from the population data obtained from 141 unrelated healthy Buryat adults. Gene frequencies of class I antigens A2, A24, A1, B61, Cw10, and Cw6 were estimated to be more than 10%. For class II, DR4, DR7, DR13, DQ7, and DQ1 antigens were predominant. A phylogenetic tree was constructed based on HLA gene frequencies, and the Buryat population was clustered with the Mongoloid groups in Northeast Asia. In the analysis of HLA-A, C, B, DR, and DQ five-locus haplotype frequencies, seven kinds of haplotypes were calculated to occur at frequencies of more than 2%. Five of the seven common haplotypes have also been described in the other human populations thus far. Some of the haplotypes have been described in European populations, while the others were shared with Northeast Asian Mongoloids as well as Amerindians. Similar situation was also found in the analysis of class I (HLA-A, C, B) three locus haplotypes. These observations suggest the unique genetic background of this Buryat population.