HCV genotype as a predictor of response to interferon therapy in patients with chronic hepatitis C

Hepatitis C virus(HCV) genotype is one of the most important predicting factors of response to interferon(IFN) therapy in patients with chronic hepatitis C. According to the molecular evolutionary analysis, HCV is classified into six major genotypes. The patients infected with genotype 1 show high HCV RNA levels and poor response to IFN therapy compared to those with genotype 2 or 3. No sufficient data are observed on response to IFN in patients with genotype 4 to 6. When PEG-IFN plus ribavirin therapy is introduced, high proportion of patients without genotype 1 must show complete response. In the near future, to predict good response to IFN therapy, it will be necessary to know whether patients have HCV genotype 1 or not.