Objective: To investigate the association between HLA-DP gene polymorphism and the susceptibility to hepatitis B virus (HBV) infection in people in Buyi, Miao and Shui ethnic groups in Guizhou.
Methods: A total of 256 patients with HBV infection, 142 HBV self-cleared patients and 135 controls were recruited from 3 ethnic groups for this case-control study. Genotypes of rs3077 and rs9277535 were determined by using real-time PCR with a TaqMan-MGB probe.
Results: Compared with healthy subjects and self-cleared subjects, the allele distribution of rs9277535 was significantly associated with chronic HBV infection (P<0.05), no significant differences in rs3077 allele and genotype distributions were found among 3 groups (P>0.05). Compared with the rs9277535 GG genotype, the AA and AG genotypes were protective factors against HBV infection in dominant model after adjustment for age and sex (OR=0.645, 95%CI: 0.421-0.988), and no significant difference in rs3077 locus was found in the same analysis (P>0.05). For men, the rs3077 locus CC and CT genotypes were also protective factors against HBV infection (OR=0.493, 95%CI: 0.266-0.916), and there was no significant difference in rs9277535 locus compared the genotype distributions among 3 groups in dominant mode. Comparison of allele and genotype distribution in 3 ethnic groups showed that HLA-DP gene rs3077 genotype distributions had significant difference between the HBV infection group and the healthy control group in Buyi ethnic group (χ(2)=6.726, P=0.036).
Conclusions: The presence of rs9277535A allele atHLA-DP gene polymorphisms might decrease the risk for HBV infection, the rs3077 C allele at HLA-DP gene polymorphisms might also confer protective effect against HBV infection in women. No significant correlation between HLA-DP gene rs3077 and rs9277535 locus polymorphism and HBV clearance was found in this study. The HLA-DP gene rs3077 genotype distribution of HBV-infected patients had significant differences among different ethnic groups.