Distributions of HLA-A and-B alleles and haplotypes in the Yi ethnic minority of Yunnan, China: relationship to other populations

Objective: To investigate the distributions of human leukocyte antigen (HLA)-A and-B alleles and HLA-A-B haplotypes in the Yi ethnic minority of the Yunnan Province, situated in southwestern China. Methods: DNA typing for HLA-A and-B loci was performed using the polymerase chain reaction-sequence-based typing (PCR-SBT) method on 114 randomly selected healthy individuals of the Yi population. The allelic frequencies of HLA-A and-B loci were calculated by direct counting and HLA-A-B haplotypes were estimated using the expectation maximization algorithm. Results: A total of 17 HLA-A and 38 HLA-B alleles were found in the Yi population. The most frequent alleles were A2402 (32.46%), A1101 (26.32%), and A0203 (10.09%) at the HLA-A locus and B4601 (12.28%), B1525 (10.09%), B4001 (8.77%), and B3802 (7.89%) at the HLA-B locus. The predominant HLA-A-B haplotypes were A2402-B1525 (7.86%) and A0203-B3802 (5.64%), followed by A1101-B4001 (4.69%). Phylogenetic analysis indicates that the Yi population in the Honghe, Yunnan Province of China basically belongs to groups of southeastern Asian origin, but shares some characteristics with northeastern Asian groups. Conclusion: The present study may add to the understanding of HLA polymorphism in the Yi ethnic group that was poorly defined previously, and provide useful information for bone marrow transplantation, anthropological research, and forensic sciences as well as for disease-association studies.

Allelic frequency distributions of 21 non-combined DNA index system STR loci in a Russian ethnic minority group from Inner Mongolia,China

We studied the allelic frequency distributions and statistical forensic parameters of 21 new short tandem repeat(STR)loci and the amelogenin locus,which are not included in the combined DNA index system(CODIS),in a Russian ethnic minority group from the Inner Mongolia Autonomous Region,China.A total of 114 bloodstain samples from unrelated individuals were extracted and co-amplified with four fluorescence-labeled primers in a multiplex polymerase chain reaction(PCR)system.Using capillary electrophoresis,the PCR products of the 21 STR loci were separated and genotyped.A total of 161 alleles were observed in the Russian ethnic minority group,and corresponding allelic frequencies ranged from 0.0044 to 0.5965.The 21 non-CODIS STR loci of the Russian ethnic minority group were characterized by high genetic diversity and therefore may be useful for elucidating the population's genetic background,for individual identification,and for paternity testing in forensic practice.