title: [Distribution of HIV-1 subtypes among different populations in Dehong prefecture, Yunnan province, in 2011].
abstract: OBJECTIVE
  To investigate the distribution of HIV-1 subtypes in Dehong prefecture, Yunnan province, in 2011.
  
  
  METHODS
  300 HIV-1 positive plasma samples were collected from Jan. 2011 to May 2011 in Dehong prefecture. HIV-1 gag genes and env genes were amplified by nested-polymerase chain reaction (PCR) from viral RNA. After sequencing, the HIV-1 subtypes were determined by phylogenetic analysis.
  
  
  RESULTS
  Based on the phylogenetic trees of gag gene and env gene fragments, a total of 222 samples were genotyped. Subtype C was the predominant strain in Dehong (43.2%, 96/222), followed by unique recombinant forms (URFs, 27.0%, 60/222), CRF01_AE (21.2%, 47/222), CRF08_BC (5.0%, 11/222), B' (2.3%, 5/222) and CRF07_BC (1.4%, 3/222). Subtype C strains were predominant in both heterosexually transmitted population and intravenous drug users (IDUs), but different subtype distribution patterns were found in these two populations. All 6 genotypes including subtype C (40.7%, 70/172), CRF01_AE (25.0%, 43/172), and URFs (25.0%, 43/172) found in this area among heterosexually transmitted population, which showed the diversity of genotypes in this population. Except subtype B' and CRF07_BC, the other 3 subtypes and URFs were detected among IDUs, mainly including subtype C (54.8%, 23/42) and URFs (38.1%, 16/42), which showed the concentration trend of genotypes distribution among IDUs. The proportion of URFs increased significantly in this area, including the new BC recombinants (41.7%, 25/60) and CRF01_AE relative URFs (58.3%, 35/60). However, the distributions of these two URFs among heterosexually transmitted population and IDUs showed no statistical significance.
  
  
  CONCLUSIONS
  The distribution of HIV-1 strains prevailing in Dehong prefecture was diversity, including 5 subtypes and a variety of URFs, of which subtype C was the predominant strain. The distribution patterns of subtype were different among different populations.
authors.affiliation: Yunnan Provincial Center for Disease Control and Prevention, Kunming 650022, China.
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Shi-tang
authors.initials: ST
authors.lastname: Yao
authors.forename: Yan-ling
authors.initials: YL
authors.lastname: Ma
authors.forename: Xiang
authors.initials: X
authors.lastname: He
authors.forename: Ji-bao
authors.initials: JB
authors.lastname: Wang
authors.forename: Chun-lin
authors.initials: CL
authors.lastname: Cheng
authors.forename: Jin
authors.initials: J
authors.lastname: Yang
authors.forename: Ying-zhen
authors.initials: YZ
authors.lastname: Su
authors.forename: Yan-ling
authors.initials: YL
authors.lastname: Li
authors.forename: Song
authors.initials: S
authors.lastname: Duan
authors.forename: Hui-chao
authors.initials: HC
authors.lastname: Chen
authors.forename: Li-Ru
authors.initials: LR
authors.lastname: Fu
authors.forename: Man-hong
authors.initials: MH
authors.lastname: Jia
authors.forename: Lin
authors.initials: L
authors.lastname: Lu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002681:China / Q000453:epidemiology; D005260:Female; D005838:Genotype; D015658:HIV Infections / Q000453:epidemiology* / Q000821:virology*; D015497:HIV-1 / Q000145:classification* / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000235:genetics; D055815:Young Adult
chemical_list: D012367:RNA, Viral