Establishment and application of HCV genotyping based on NS5B region

Objective To establish a sensitive and efficient method for differentiation of HCV genotype 6a based on non-struc-tural protein(NS) 5B region,and to investigate whether HCV genotyping based on NS5B region is consistent with that based on 5'-noncoding region(NCR).Methods HCV genotyping based on 5'-NCR was performed on 1093 HCV RNA positive serum samples,and then the NS5B region of HCV genotype 6a serum samples was amplified.Enzyme analysis and sequencing were performed on the second PCR products and the genotype was verified by NCBI Genotyping.Results Ten HCV genotype 6a serum samples were obtained by HCV genotyping based on 5'-NCR,and sequence analysis showed CA insertion at position 145 and C insertion at posi-tion 139 existed in this region.The 10 HCV genotype 6a serum samples were verified by HCV genotyping based on NS5B region,and sequence analysis confirmed the existence of Eae I restriction site in NS5B region.Conclusions HCV genotyping for genotype 6a based on NS5B region is consistent with that based on 5'-NCR.HCV genotyping based on Eae I restriction sites of NS5B region is available for clinical practice.