[Subtype and sequence analysis of the C2-V3 region of gp120 genes among HIV-1 strains in Sichuan province]

Zhonghua Liu Xing Bing Xue Za Zhi. 1998 Feb;19(1):39-42.
[Article in Chinese]


Nine DNA fragments of HIV-1 env gene were amplified by PCR from uncultured peripheral blood mononuclear cells (PBMCs) obtained from HIV-1 sero-positive intravenous drug users (IDUs) in Sichuan province, in mid 1996. Their C2-V3 region (about 450 bp) was sequenced. Sequence analysis showed that there were two HIV-1 subtypes B and C, with 1.4% and 2.6% gene divergence inside each subtype, in Sichuan. The 5 subtype B strains, when comparing with sequences of several reference HIV-1 strains, were found similar to these identified in Thailand, Myanma and Yunnan province. The nucleotide sequence divergence between them was ranged from 3.6% to 4.3%. Meanwhile, the 4 subtype C strains except sc3, were most close to those found in India as well as in Yunnan province, and both their nucleotide sequence divergence was 3.1%. The sc3 strain belonged to subtype C but had larger genetic distance, between 10.1%-17.2%. Above results suggested a recent epidemic of both subtype HIV-1 strains in Sichuan provine and they were very close to those identified in Yunnan province: The subtype C strain of sc3 is special and its source remains not clear.

Publication types

  • English Abstract

MeSH terms

  • China
  • DNA, Viral / genetics
  • Genes, Viral*
  • Genetic Variation*
  • HIV Envelope Protein gp120 / genetics*
  • HIV Seropositivity / virology
  • HIV-1 / classification
  • HIV-1 / genetics*
  • Humans
  • Polymerase Chain Reaction
  • Sequence Analysis, DNA


  • DNA, Viral
  • HIV Envelope Protein gp120