Conserved nucleotide sequence of NS5A in hepatitis G virus or GB virus C in Japan and China

Abstract

A semi-nested PCR method was designed for detecting the NS5A region of hepatitis G virus (HGV) or GB virus C (GBV-C) using specific oligonucleotide primers. Patients, 14 of 69, suffering from hepatic diseases in Japan and 5 of 21 in China showed strong positive signals for HGV or GBV-C by this method. The PCR products were directly sequenced. The nucleotide sequences identified differed from one another by 0–5%, from HGV by 3–9% and GBV-C by 2–7%, the percentages of the latter two being compared with the sequences reported previously. Amino acid sequences were the same or had only one alteration compared with HGV and two to three alterations compared with GBV-C. These results indicate that the nucleotide sequence of NS5A of HGV (or GBV-C) is more conserved than that of NS3 of GBV-C (or HGV) which has been reported to show variations of 0–23%.