[Cloning and sequencing of partial genes of hepatitis C virus genome in patients with acute hepatitis C].

OBJECTIVE

To explore the etiological role of HCV in patients with acute hepatitis.

METHODS

The prevalence of HCV infection in 89 patients with acute hepatitis was investigated by analysis of HCV RNA and HCV second generation antibody. HCV RNAs extracted from the sera of 5 patients with NANB acute hepatitis, which were positive for HCV RNA, were converted to cDNA by reverse transcription with random primer and genotyping by PCR with type-specific primers. The partial genes of HCV genome were amplified. The PCR products were expressed in E. coli with p-GEM-T vector, and their nucleotide sequences were determined by dideoxynucleotide chain-termination method.

RESULTS

The incidence of hepatitis virus infection was 47. 2% in HAV, 28.1% in HBV and 15.7% in HCV, respectively. The incidence of HAV and HBV coinfection was 14.6% and the rate of non-A, non-B and non-C hepatitis was 9% in all patients. The genotype of HCV-RNA positive patients was 85.8% in HCV-II, 7.1% in HCV-III and 7. 1% in combining HCV-II/III, respectively. The partial sequence of HCV genome in 5 patients with non-A and non-B acute hepatitis was amplified and the fragment was 424 bp in accordance with original design. The homology of the sequences was 98.1%-99.5% in nucleotide acid and 97.6%-99.2% in amino acid among five isolates. The average homology was 91.9% or 94.3%-95.6% for nucleotide sequences between HCV-I or HCV-II and the 5 isolates, and 92.3%-95.8% for amino acid sequences between the 5 isolates and HCV-I or HCV-II, respectively.

CONCLUSION

HCV infection is one of the main hepatitis viruses in patients with acute hepatitis, in which the HCV-II genotype is dominant and should be paid attention to it.