Typing hepatitis C virus by polymerase chain reaction in blood donors.

Hepatitis C virus (HCV) genomes were recently detected in biological materials, and were divided into types I, II, III and IV according with their nucleotide sequences variations.In this study, typing of the HCV genomes was performed in 84 PHA-positive and HCV-RNA-positive blood donors in Yamanashi Prefecture.A typing method developed by Dr. Okamoto was used, depending on the amplification of a C gene sequence by polymerase chain reaction (PCR) using a universal primer (sense) and a mixture of four type-specific primers (antisense). Type I was found in 1 sample (1.3%), type II was found in 56 samples (71.8%), type III was found in 12 samples (15.4%) and type IV was found in 9 samples (11.5%) out of 78 blood donors, the rest of 6 samples were not specified.The prevalence of HCV-subtype was surveyed in Yamanashi Prefecture. The result suggests that there are geographical differences of HCV subtype.Also, those samples were divided into c-100-positive group and c-100-negative group. And we compared between HCV subtype and c-100 positivity. In c-100-positive group, Type I was found in 1 sample (1.9%), type II was found in 42 samples (80.0%), type III was found in 6 samples (11.5%) and type IV was found in 3 samples (5.8%) out of 52 individuals. In c-100-negative group, Type II was found in 14 samples (53.8%x), type III was found in 6 samples (23.1%) and type IV was found in 6 samples (23.1%) out of 26 individuals.