GEOGRAPHICAL CHARACTERIZATION OF HEPATITIS-G VIRUS GENOME - EVIDENCE FOR HGV GENOTYPES BASED ON PHYLOGENETIC ANALYSIS

Recently, the genome from a novel virus, termed hepatitis G virus (HGV ) and GB virus C (GBV-C), has been discovered in the serum of patients . To investigate the heterogeneity of this viral genome, we sequenced 188 nucleotides at the 5'untranslated region (5'UTR) of HGV genome in 48 individuals from 11 different countries, including the USA. Asia (J apan, Korea, Nepal, Myanmar, Cambodia, Vietnam and Thailand), Spain, E gypt and Ghana and compared the results with these isolates. The data showed that there was a consensus genome sequence among the HGV isolat es from each country and that it could be classified into at least thr ee different groups or genotypes. Construction of phylogenetic trees, bootstrap analysis and calculation of mean distances between possible, genotypes in the 5'UTR of HGV isolates also showed three major genotyp es, which were defined as West Africa (type 1), US/Europe (type 2) and Asia types (type 3). Type 2 was found in various geographic areas, in cluding USA, Europe, Egypt and Asia, while type 1 was found predominan tly in West Africa, Type 3 was found mainly in Asia. Furthermore, type 3 could be clearly differentiated into a regional group, compared wit h the other two types, by bootstrap analysis. The HGV sequence of 5'UT R obtained from one Japanese patient showed no mutation over 12 years. These results suggest that HGV have genotypes corresponding to geneti c heterogeneity and is correlated with geographic distribution. (C) 19 98 Elsevier Science Ireland Ltd. All rights reserved.