HLA allele and haplotype frequencies in Kazakhstani Russians and their relationship with other populations.

HLA class I and class II genotypes from 947 Kazakhstani individuals of Russian origin were analyzed for investigating their most likely origin. The results were compared with similar data from other Russians (East and West), and also Worldwide populations, using standard genetic distances, neighbor-joining dendrograms, correspondence and haplotype analysis. Of the five HLA loci analyzed (HLA-A, HLA-C, HLA-B, HLA-DRB1, and HLA-DQB1) genotyped, 216 HLA alleles were identified. The most frequent alleles were A02:01 (26.5%), B07:02 (11.1%), C04:01 (13.5%) and C06:02 (12.1%), DRB107:01 (13.8%) and DRB115:01 (12.2%), and DQB103:01 (19.7%). Significant linkage disequilibrium was noted between all HLA pairs. DRB115:01 ~ DQB106:02 (10.5%), B07:02 ~ C07:02 (10.0%), B07:02 ~ DRB115:01 (6.3%), and A01:01 ~ B*08:01 (4.5%) were the most frequent two-locus haplotypes identified. Subsequent analyses showed that Kazakhstani Russians were closely related to West Russia-residing populations (Northwest Slavic, Vologda, Chelyabinsk, Moscow), East Europeans (Belarus Brest, Ukraine, Poland) and Scandinavians (Swedish, Finns), but distinct from East Russia-residing populations (Tuvians, Siberians from Chukotka, Kamchatka, and Ulchi) and East Mediterraneans (Levantines, Turks, North Macedonians, Albanians), and East Asians (Koreans, Japanese, Taiwanese, Mongolians). These results are in accordance with historical data indicating that the Russians of central Asia originate mainly from European Russia during the migratory flow of 18th and 19th centuries.