[Genetic polymorphism of Chinese Zhuang population at HLA-Cw locus by sequence based typing]

Thirst study was purposed to explore the genetic polymorphism of Chinese Zhuang population at HLA-Cw locus by sequence based typing (SBT). A total of 150 unrelated blood samples from Chinese Zhuang population were subjected to sequencing at exon 2, 3 and 4 of HLA-Cw gene in both directions by using SBT technique established by our laboratory. The purified products of sequencing reaction were run by means of electrophoresis on the ABI 3730 DNA Sequencer and the assignment of HLA-Cw genotype was accomplished by using the Assign 3.5 software. The consensus sequence at exon 2, 3 and 4 of HLA-Cw gene for each sample was imported into the Assign 3.5 software. The results showed that 33.33% of tested samples could obtain an unique genotype, genotype in 63.33% of tested samples with ambiguous results could be assigned by ruling out the rare alleles according to the NMDP Rare Allele List File; however, the final genotype in rest 3.33% of the detected samples could be defined when subjected to further confirmatory testing by PCR-SSP. In this detection 16 HLA-Cw alleles were identified, the common alleles with a frequency of > 10% were Cw*0304 > Cw*0102 > Cw*0801 > Cw*0702. The value for gene diversity (GD) was 0.9297, The frequency for Cw*01, 03, 07, 08, 12, 14 (Cw 1 allele group) and Cw*02, 04, 05, 06, 15, 16, 17, 18 (Cw 2 allele group) was 0.8967 and 0.1032, respectively, which indicated that the Cw 1 allele group is the dominant ligand for KIR in Chinese Zhuang population. 51 genotypes were determined and the distribution of genotype frequency was in line with Hardy-Weinberg principle. It is concluded that the obtained HLA-Cw allele frequency and its distribution characteristics of Chinese Zhuang population can provide valuable data in the studies of anthropology and the association of HLA-Cw with disease.