An updated analysis of hepatitis C virus genotypes and subtypes based on the complete coding region

Background: The hepatitis C virus (HCV) genomic database is expanding rapidly. Aims: There is a need to provide an updated phylogenetic tree analysis based on the complete coding region of HCV. Methods: All available HCV complete genome sequences in the HCV databases available through October 2010 were analyzed. Results: The assignment of all known complete sequences up-to-date confirmed the previous six major genotypes and one new sequence, which have been provisionally assigned as subtype 7a. New recombinant forms of HCV, although uncommon, have been detected and were found to have different crossover points. Conclusion: This updated analysis based on the complete region of HCV confirmed the validity of the previously assigned genotypes/subtypes and provided an up-to-date reference for future basic research and clinical studies.