Association of human platelet antigens polymorphisms with susceptibility to hepatitis C virus infection in Chinese population.

Hepatitis C virus (HCV) is a major cause of chronic hepatitis. Previous studies have identified a number of single nucleotide polymorphisms that are associated with HCV infection. Human platelet antigens (HPAs) polymorphisms play an important role in several diseases. Here, we demonstrated the association of the HPA-2, HPA-3, HPA-5 and HPA-15 polymorphisms with susceptibility to HCV infection in Chinese population. Overall, 118 patients with HCV and 167 controls were genotyped for HPAs. There were no significant differences in the allele and genotype frequency distribution for the HPA-3, HPA-5 and HPA-15 systems between the patients with chronic HCV infection and the healthy controls (p > .05). However, the genotype frequency of HPA-2aa was significantly lower, while HPA-2ab/bb was significantly higher in patients than that in the controls (p = .006). The allele frequency of HPA-2a in patients was significantly lower than that in the control group (p = .005). In contrast, HPA-2b in patients was significantly higher than that in the control group (p = .005). We conclude that HPA-2 polymorphism is associated with susceptibility to HCV infection, and individuals carrying the HPA-2b allele may have a higher risk of HCV infection compared with individuals carrying HPA-2a.

High-resolution HLA-A, -B and -DRB1 allele and haplotype frequencies in 7823 Han marrow donors of Liaoning province, China.

BACKGROUND: The human leukocyte antigen (HLA) system is the most polymorphic gene cluster in humans. High-resolution donor-recipient matching for HLA genes improves patient survival after unrelated hematopoietic stem cell transplantation. MATERIALS AND METHODS: In this study, we analyzed the high-resolution allele and haplotype frequencies at the HLA-A, -B and -DRB1 loci in the Liaoning Han population and analyzed its relationships with other populations. RESULTS: The 3 most frequent alleles at the HLA-A, -B and -DRB1 loci were A*24:02, A*02:01:01G, A*11:01; B*13:02, B*46:01, B*40:01:01G; DRB1*09:01, DRB1*15:01 and DRB1*07:01, respectively. The most frequent 2-locus haplotypes were A*30:01-B*13:02 and B*13:02-DRB1*07:01. A*30:01-B*13:02-DRB1*07:01 was determined to be the predominant 3-locus haplotype. Hot maps and multiple correspondence analyses based on the frequencies of HLA specificities, which allow statistical visualization of dependent and independent relationships among variables, indicate that the Liaoning Han population is closely related to Northern populations of China and shows relative close relationships with Asian populations. CONCLUSION: These data will provide an outline of the HLA characteristics of healthy individuals in our region and help bone marrow transplantation patients find suitable HLA-matched donors.

HLA-A, HLA-B, HLA-DRB1 allele and haplotype frequencies of 14,529 Chinese Han bone marrow donors living in Dalian, China.

We investigated the allele and haplotype frequencies of HLA-A, HLA-B and HLA-DRB1 loci in Dalian Chinese Han population using blood samples of unrelated marrow donors who live in Dalian. The genetic relationship between Dalian and different regions worldwide was further explored based on HLA status of different populations. A total of 14,529 samples were genotyped at 2-digit level only by sequence-specific oligonucleotide and sequence-based typing methods. Allele frequencies of HLA-A, HLA-B and HLA-DRB1 were calculated by the direct counting method. Haplotype frequencies and linkage disequilibrium (LD) values were calculated by the maximum likelihood method. F(ST) values were calculated by allele frequency data of each locus. Phylogeny tree of Nei's DA genetic distances was constructed by the UPGMA method. HLA-A*02 was the most frequent allele at HLA-A locus followed by A*11 and A*24. Alleles at HLA-B locus ranked in decreasing order by frequency were B*40, B*15 and B*13. The three highest frequency alleles were DRB1*15, DRB1*09 and DRB1*12 at HLA-DRB1 locus. A*30-B*13-DRB1*07 was the most frequent three-locus haplotype. For the population relationships, Dalian had a relative close genetic relationship with Liaoning and Yantai-Weihai and a relative distant genetic relationship with Australia. The information obtained in this study may provide useful information for anthropological studies, for disease-association studies and helping bone marrow transplantation patients to search HLA-matched donors.