Frequency of the HLA-DP genes and the antigens of the HLA-A, -B, -Cw, and -DR loci in Tuvinians

The results of DNA typing of the HLA-DPB1 gene among Tuvinians are described. The allele 0201 was found to be the most frequent (26.66%); then, in order of decreasing frequency, followed the alleles 0401 (26.42%), 0402 (13.99%), 0301 (8.55%), 0501 (7.77%), 0901 (5.16%): and 1301 (2.07%). The frequency of the allele 0501 in Tuvinians was significantly lower than that in the published data on allele distributions characteristic of two other Mongoloid populations, the Manchu and Japanese. The results of the serological typing of the loci HLA-A, -B, and -Cw of class I in the Tuva population were compared to the corresponding published data on ten Mongoloid populations of Central and Eastern Asia: Uigurs, Kazakhs, Mongols, Manchu, Tibetans, the Chinese of the northern and southern regions of China, Thais (inhabitants of Northwestern Indochina), Koreans, and Japanese. In Tuvinians, the most frequent antigens were HLA-A2, -A9, -B0, -B35, -B17, -Cw4, and -DR5. In the inhabitants of Tuva, the frequency of the antigens HLA-A1, -A9, -B17, -Cw2, and -Cw4 was significantly higher than in other Mongoloids, while that of the antigens HLA-A26 and -B22 was lower. This difference was greatest in the case of antigen HLA-B40: it a frequency of 43.4% was detected in it, while in individuals of Mongolian origin, the frequency of this antigen did not exceed 22.5%. Indices of genetic similarity (IGSs), calculated from the gene frequencies of the loci HLA-A, -B, and -Cw, suggested that the Tuvinians were most closely related to Kazakhs (IGS = 0.73), and least related to the Japanese and Uigurs (IGS = 0.66); Our data suggest that Tuvinians significantly differ from the compared populations of Central and Eastern Asia.