HLA-A, HLA-B, and HLA-DRB1 alleles and haplotypes in Naxi and Han populations in southwestern China (Yunnan province).

The frequencies of the human leukocyte antigen alleles HLA-A, HLA-B, and HLA-DRB1 and the A-B-DRB1, A-B, and B-DRB1 haplotypes were studied in Naxi and Yunnan Han populations using polymerase chain reaction (PCR)-sequence-specific amplification for alleles A and B and a PCR-microtiter plate hybridization method for the DRB1 allele. A total of 8 A, 19 B, and 30 DRB1 alleles were found in the Naxi population, and 15 A, 21 B, and 36 DRB1 alleles were found in Yunnan Han population. The common A-B-DRB1 haplotypes in the Naxi population were A24-B15-DRB11202, A11-B15-DRB10405, A11-B15-DRB11202, A11-B38-DRB108032, and A11-B55-DRB10405; the common A-B haplotypes were A11-B15, A11-B38, and A24-B15; and the common B-DRB1 haplotypes were B15-DRB11202, B38-DRB108032, and B48-DRB11201. In the Yunnan Han population, the common A-B-DRB1 haplotypes were A24-B15-DRB11501, A24-B46-DRB108032, and A24-B15-DRB11201; the common A-B haplotypes were A24-B15, A24-B46, and A34-B46; and the common B-DRB1 haplotypes were B15-DRB11501, B46-DRB109012, and B46-DRB11401. Phylogenetic tree and principal component analyzes based on HLA-A, HLA-B, and DRB1 allele frequencies suggested that the Naxi ethnic group belongs to the southern Chinese groups, while the Yunnan Han population is a characteristic population located intermediate between northern and southern Chinese groups, although they live in the southwest of China.