CONSERVED NUCLEOTIDE-SEQUENCE OF NS5A IN HEPATITIS-G VIRUS OR GB VIRUS-C IN JAPAN AND CHINA

A. semi-nested PCR method was designed for detecting the NS5A region o f hepatitis G virus (HGV) or GB virus C (GBV-C) using specific oligonu cleotide primers. Patients, 14 of 69, suffering from hepatic diseases in Japan and 5 of 21 in China showed strong positive signals for HGV o r GBV-C by this method. The PCR products were directly sequenced. The nucleotide sequences identified differed from one another by 0-5%, fro m HGV by 3-9% and GBV-C by 2-7%, the percentages of the latter two bei ng compared with the sequences reported previously. Amino acid sequenc es 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 th an that of NS3 of GBV-C (or HGV) which has been reported to show varia tions of 0-23%. (C) 1997 Elsevier Science Ireland Ltd.