Mutations in a hydrophilic part of the core gene of hepatitis C virus in patients with hepatocellular carcinoma in China

We investigated the association between hepatocellular carcinoma (HCC) and the genomic characteristics of the hepatitis C virus (HCV) isolated from residents of the inshore region of the Yangtze River, an area that has one of the highest incidence of HCC in China. We determined the genomic heterogeneity of HCV, and the sequence divergence of the HCV core gene in individuals with chronic hepatitis and HCC. HCV genotype II was predominant among these isolates, which were homologous to other Chinese and Japanese HCV isolates. The rate of nucleotide substitutions in the core gene was significantly greater for isolates from HCC patients than for those from individuals with chronic hepatitis. The nucleotide substitutions were unevenly scattered along the core gene; a cluster of missense mutations was apparent in the region encoding the second hydrophilic domain of the core protein. The rate of occurrence of missense mutations per nucleotide substitution was significantly greater in this clustering variable region (CVR) of the core gene than in the remaining core gene sequence. These observations suggest that mutations in the CVR may be involved in the pathogenesis of chronic HCV infection during hepatocellular carcinogenesis.