[Association of HLA-DQ and IFNL4 polymorphisms with hepatitis B virus infection and clearance]

Objective: To confirmed the polymorphisms of HLA-DQ and IFNL4 were associated with HBV infection and clearance in a Chinese population. Methods: The Sequenom MassARRAY MALDI-TOF system was used to genotype the HLA-DQrs9275319 and IFNL4rs368234815, rs12971396, rs12979860, and rs8099917. A binary logistic regression test was conducted to estimate the relative risk of these SNPs with HBV infection and clearance. Haploview4.2 software and PHASE software (v2.0.2) were employed to analyze linkage disequilibrium (LD) and haplotype frequencies. The MDR program was applied to analyze interactions between SNP and SNP.Statistical analysis was performed using SPSS 19.0 and P-values were corrected by Bonferroni's corrections. Results: A total of 1,069 subjects were recruited and divided into three groups: 238 healthy controls(HC), 397 with HBV-related chronic liver disease (CLD), 434 with spontaneous clearance (SC). The rs9275319TT was most frequently identified among all groups(86.2% in the CLD group, 77.6% in the SC group, and 75.9% in the HC group).Carriage of the rs9275319 C allele was a protective factor for chronic HBV infection (the allele model: P = 0.000 3, OR,0.514; 95% CI, 0.359-0.738) and clearance (the allele model: P = 0.002, OR, 1.659; 95% CI, 1.197-2.300). HLA-DQ rs9275319 showed a significant association with HBV infection (allele model, OR, 0.514; 95% CI, 0.359-0.738, adjusted P = 0.000 3) and spontaneous clearance (allele model, OR, 1.659; 95% CI, 1.197-2.300, adjusted P = 0.002). However, there was no association between IFNL4 polymorphism and HBV infection((allele model: P = 0.082 for rs368234815; P = 0.063 for rs12971396; P = 0.517 for rs12979860; P =0.695 for rs8099917) or spontaneous clearance ((allele model: P = 0.358 for rs368234815; P = 0.105 for rs12971396; P = 0.640 for rs12979860; P = 0.640 for rs8099917;all P > 0.05). The multifactor dimensionality reduction (MDR) test showed there was a three-way interaction (rs12971396, rs12979860, and rs9275319) between IFNL4 and HLA-DQ polymorphisms for HBV infection (permutation P = 0.009 for the best factor model) and clearance (permutation P = 0.014 for the best factor model). Conclusion: The SNP-SNP interaction between HLA-DQ and IFNL4 is associated with the regulation of HBV infection and natural clearance.