丙型肝炎是由丙型肝炎病毒(HCV)引起的急、慢性传染病。丙型肝炎流行广泛，慢性化率高达50%～85%，并可转化为肝硬化和肝细胞癌。目前慢性丙型肝炎（CHC）的标准治疗方案为聚乙二醇干扰素联合利巴韦林，但约50%的HCV 1型患者不能获得持续病毒学应答。研究发现，HCV 基因型、病毒载量，以及宿主性别、年龄、乙醇摄入量、肝纤维化程度、合并感染、基因多态性等因素可影响治疗效果。其中，HCV病毒载量、HCV基因型及宿主基因多态性是预测持续病毒学应答的重要因素，可用于制订个体化治疗方案。

Hepatitis C, caused by infection of hepatitis C virus (HCV), is an acute or chronic infectious disease involved with a significant proportion of population worldwide. In general, 50%-85% of the infections might become chronic hepatitis C or carriers, thereafter developing into cirrhosis and hepatocellular carcinoma. Currently, the standard of care for chronic hepatitis C is pegylated interferon α (PEG-INFα) plus ribavirin (RBV). Nevertheless, about 50% of the patients infected with HCV genotype 1 fail to achieve sustained virological response (SVR) although they share the same or similar diagnosis. A number of clinical studies show that the efficacy of standard of care depent on both virus and host factors. The predictors of SVR on the HCV side include viral load and genotype; on the host side, gender, age, alcohol consumption, fibrosis stage, co-infection with other virus, genetic polymorphisms are included. Among those, the most important elements that may play significant roles in the individualized treatment of HCV infections are the viral load and genotype as well as the variation in the host gene interleukin 28B (IL-28B).