Comparison of sequence diversity in genotype Ⅱ and Ⅲ hepatitis C virus(HCV) hypervariable region 1(HVR1) in Chinese / 第二军医大学学报

ABSTRACT

Objective: To compare the sequence diversity of HVR1 in the putative envelope protein E2 of the genotypeⅡand genotype Ⅲ HCV in Chinese. Methods: The cDNAs[nucleotide(nt)1449-1586(HCV-J) or nt1460-1582(HCV-J6)] derived from plasma of 55 patients infected with genotype Ⅱ HCV and 38 patients infected with genotype Ⅲ HCV were amplified,purified and directly sequenced by RT-nested polymerase chain reaction(PCR) and dideoxynucleotide chain termination method. Results: The HVR1 was found in amino acid(aa) 384-408 positions of both types HCV E2 protein. There were 5 similar conserved amino acids in 2 types HCV HVR1aa385(Thr), aa389, 390, 406(Gly)and aa403(Phe).Besides, 401(Ser) was also highly conserved in genotype Ⅱ HCV HVR1. Although the variation characteristic of 2 types was similar, but the sequence diversity(SD),the kinds and frequency of some amino acids in some HVR1 positions and the conserved region near the HVR1 had some differences between 2 genotypes. Conclusion: Further study on the diversity of HVR1 and its biological significance will be helpful to understand the mechanism of HCV persistent infection and the development of HCV vaccine.