Conflicting selection pressures target the NS3 protein in hepatitis C virus genotypes 1a and 1b.

ABSTRACT: Analysis of complete polyprotein-encoding sequences of the two most prevalent genotypes of hepatitis C virus (HCV-1a and HCV-1b) revealed evidence of abundant, slightly deleterious nonsynonymous variants subject to ongoing purifying selection. In the case of both HCV-1a and HCV-1b, the NS3 protein demonstrated a high incidence of forward-and-backward or parallel nonsynonymous changes in CTL epitopes as measured by the phylogenetic consistency index. These results imply that certain nonsynonymous mutations have occurred frequently throughout the HCV-1a and HCV-1b phylogenies in the codons encoding the epitopes in NS3. This pattern is best explained by the frequent re-occurrence of the same set of escape mutations in CTL epitopes of NS3, which are selectively favored within hosts presenting

SUBMITTER: Irausquin SJ 

PROVIDER: S-EPMC3529174 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature