Distinct HLA allele and haplotype distributions in four ethnic groups of China.

Distinct human leukocyte antigen (HLA) allele and haplotype distributions occur in the northern and southern Han populations of China. However, different ethnic groups in China show limited regional distributions for many HLA alleles and haplotypes. Therefore, it is necessary and meaningful to study the differences in HLA allele and haplotype distribution for northern and southern ethnic groups of China. A total of 428 unrelated individuals from the Lisu, Nu, Tu and Yugur ethnic populations were genotyped for HLA-A, -B, -C and -DRB1 alleles using the PCR-Luminex typing method. The frequencies of HLA alleles and statistically inferred haplotypes were calculated. A total of 29 HLA-A, 54 HLA-B, 27 HLA-C and 41 HLA-DRB1 alleles were spread throughout these four populations with distinct allele and deduced haplotype frequencies between populations. Some alleles and deduced haplotypes exhibited significantly different distributions between northern (Tu and Yugur) and southern groups (Lisu and Nu). A phylogenetic tree and principal component analysis were used to compare the HLA polymorphism between our dataset and 19 other eastern and southeastern Asian populations. This analysis showed that Lisu and Nu belong to a cluster of southern ethnic groups, while Tu and Yugur are most closely related to other northern groups. Thus, distinct ethnic population histories were revealed by analyzing HLA allelic polymorphisms with the HLA profiles of the Lisu and Nu southern Chinese ethnic groups clearly different from the Tu and Yugur northern ethnic groups. The results will be useful for future association studies of infectious disease and contribute toward a more efficient search of organ/tissue matches for transplantation.