title: [Development of a rapid subtype-screening assay for the env region of HIV-1 CRF strains in Guangxi.].
abstract: BACKGROUND
  To develop a simple and rapid subtype-screening assay for the env region of the circulating recombinant form (CRF) of human immunodeficiency virus type 1 (HIV-1) in Guangxi.
  
  
  METHODS
  Proviral DNA from HIV-1 positive samples were extracted and subjected to the first round PCR with universal primers for the env region that can detect HIV-1 M group isolates. In the second round PCR, two pairs of subtype-specific primers that were designed to detect subtype C or B'/C and CRF01-AE respectively were added into one tube. The PCR products of different subtypes could be distinguished in agarose-gel electrophoresis. Additionally, all of these samples were sequenced and analyzed phylogenetically.
  
  
  RESULTS
  Phylogenetic analysis of the env region of 50 samples showed that 3 samples (6%) were infected with CRF08-BC, 43 (86%) with CRF01-AE, and 4 (8%) remained unclassifiable. Detection of the subtype-specific primer sets revealed that 3 were subtype C or B'/C (100%), 39 were CRF01-AE (90.7%), with an adequate sensitivity (91.3%) and a high specificity (100%). Non-specific bands occasionally appeared but did not interfere with interpretation of the results. The phylogenetic analysis was consistent with subtype-specific primer sets and the consistency rate was 92%. The average reproducibility was 100% for CRF08-BC samples and 93.8% for CRF01-AE samples.
  
  
  CONCLUSIONS
  A simple, rapid and low cost assay was developed for subtype-screening of CRF01-AE in Guangxi.
authors.affiliation: Guangxi Medical University, Nanning 530021, China.
authors.forename: H
authors.initials: H
authors.lastname: Liang
authors.forename: H
authors.initials: H
authors.lastname: Luo
authors.forename: Y M
authors.initials: YM
authors.lastname: Shao
authors.forename: W
authors.initials: W
authors.lastname: Liu
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Xing
authors.forename: C J
authors.initials: CJ
authors.lastname: Lu
authors.forename: J
authors.initials: J
authors.lastname: Shen
authors.forename: Z D
authors.initials: ZD
authors.lastname: Mai
mesh_terms: D002681:China; D015658:HIV Infections / Q000821:virology; D015497:HIV-1 / Q000235:genetics; D006801:Humans; D010802:Phylogeny; D015203:Reproducibility of Results