GENOTYPE DISTRIBUTION AND COMPARISON OF THE PUTATIVE ENVELOPE REGION OF HEPATITIS-C VIRUS FROM KOREAN PATIENTS

Comparative nucleotide sequence studies of the genomes of hepatitis C virus (HCV) revealed that there are at least 6 different genotypes of HCV. The prevalence of HCV genotypes among the patients with liver dis eases in Korea was investigated using the polymerase chain reaction (P CR) for the NS5 region. In the 75 HCV RNA positive samples, two genoty pes, type 1b and type 2a, were the major causative agents which accoun ted for 60% and 33% of infections respectively, while 7% could not be assigned a genotype by the methods used. The nucleotide sequences of c DNAs encoding the putative envelope proteins from 10 type 1b and 5 typ e 2a genotype samples were analyzed. Approximately 31-42% of the nucle otide sequences of type 1b samples examined differed from those of dif ferent genotypes. In the case of type 2a samples, 36-42% of the nucleo tide sequences differed from those of different genotypes. The diversi ties of the amino acid sequences were the same or greater than those o f the nucleotide sequences. Two hypervariable regions (HVR1 and HVR2) were recognized in both HCV genomes of genotypes 1b and 2a. However, t he sequence divergence within the HVR2 region of genotype 2a was less than that of genotype 1b. (C) 1995 Wiley-Liss, Inc.