Interferon-λ-related genes and therapeutic response in Chinese hepatitis C patients

Polymorphisms of HLA-DM on Treatment Response to Interferon/Ribavirin in Patients with Chronic Hepatitis C Virus Type 1 Infection

Background: HLA-DM gene, which is related to antigen processing and presentation and located in the non-classical class-II region of human leukocyte antigen (HLA) region, may play a crucial role in chronic hepatitis C virus (HCV) infection treatment outcomes. The study was conducted to evaluate the role of the variant of several single nucleotide polymorphisms (SNPs) in HLA-DM gene in HCV treatment outcomes. Methods: We genotyped four SNPs from the candidate genes (HLA-DMA and DMB) in 336 patients who were treated with pegylated interferon-alpha and ribavirin (PEG IFN-α/RBV). Multivariate analysis of factors predicting sustained virological response (SVR) was conducted. Results: HLA-DMA rs1063478 and DMB rs23544 were independent factors of HCV treatment outcomes in Chinese Han population. Individuals who carried favorable genotypes of rs1063478TT and rs23544GG were more likely to achieve SVR {Dominant model: odds ratio (OR) = 2.05, 95% confidence interval (CI) = 1.24–3.41; OR = 2.04, 95% CI =1.23–3.35, respectively}. Rs23544, rs1063478, baseline glucose, baseline platelet and T4 level were independent predictors of SVR. The area under the receiver operating characteristic (ROC) curve (AUC) was 0.740. Conclusions: The genetic variation of rs1063478 and rs23544 are associated with the treatment outcomes in the Chinese Han population.

A novel polymorphism near HLA class II region is associated with spontaneous clearance of HCV and response to interferon treatment in Chinese patients

A recent genome-wide association study (GWAS) has identified the single-nucleotide polymorphism (SNP) rs4273729 in a 100-kbp region comprising human leukocyte antigens (HLAs) class II genes as an important predictor of hepatitis C virus (HCV) clearance in European and African populations. This study was to determine whether this polymorphism is also associated with spontaneous HCV clearance as well as response to interferon treatment in Chinese patients. Thus, 686 chronic HCV carriers, 432 individuals with spontaneous viral clearance and 243 patients with pegylated interferon-α and ribavirin (PEG IFN-α/RBV) treatment were genotyped. The rs4273729 GG genotype was strongly associated with spontaneous HCV clearance as well as better IFN/RBV treatment response compared with the GC/CC genotypes in Chinese Han population (additive model: odds ratio (OR)=0.62, 95% confidence interval (95% CI)=0.51-0.76; OR=0.58, 95% CI=0.38-0.88, respectively). Rs4273729, rs12980275, baseline HCV RNA and platelet level were independent predictors for sustained virological response (SVR). The area under the receiver-operating characteristic curve (AUC) was 0.578 when including rs4273729 alone, but the prediction value was improved significantly (AUC=0.733) when further including rs12980275, baseline viral load and baseline platelet level. In conclusion, the genetic variation of rs4273729 is associated with clearance of HCV in both the natural course and the treatment process in Chinese Han population.