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

AIM: To determine the association between rapid viral response and IL28B, IL28RA, IL10RB and MxA polymorphisms in the Chinese Han population. METHODS: The study cohort consisted of 238 chronic hepatitis C patients treated with interferon (IFN)-alpha-2b and ribavirin. Six single nucleotide polymorphisms were genotyped using the ABI TaqMan allelic discrimination assay. Biochemical indices were measured at baseline. Serum hepatitis C virus (HCV) RNA was detected at weeks 0, 4, 12 and 24 of therapy. RESULTS: Only IL28B rs12980275 was associated with treatment response in the Chinese Han population. Patients carrying AG/GG genotypes had a reduced rapid viral response compared with patients carrying the AA genotype (additive model: adjusted OR = 0.43, 95% CI: 0.24-0.75). It took less time for patients with the AA genotype to achieve a viral load < 500 copies/mL (log-rank test, P = 0.004). In addition, the protective effect of genotype AA was independent of baseline viral load. HCV genotype, and baseline white blood cell count, a-fetoprotein and viral load might also help predict treatment response. The area under the receiver-operating characteristic curve was 0.726. CONCLUSION: IL28B rs12980275 AA genotype is a strong predictor of positive response to IFN therapy in Chinese Han patients with hepatitis C.