title: Molecular epidemiology of HIV-1 infection and full-length genomic analysis of circulating recombinant form 07_BC strains from injection drug users in Taiwan.
abstract: BACKGROUND
  Previously, we reported that there was an outbreak of human immunodeficiency virus type 1 (HIV-1) circulating recombinant form (CRF) 07_BC among injection drug users (IDUs) in Taiwan in 2004. The objectives of the present study were to conduct a molecular epidemiological analysis and to characterize the full-length genome of the Taiwanese CRF07_BC.
  
  
  METHODS
  Three hundred and fifty-eight patients with HIV-1/AIDS from hospitals and 133 HIV-1-infected inmates from detention centers were recruited. DNA sequencing and phylogenetic analysis were conducted to determine subtypes and evolutionary relationships. Recombination breakpoints of 2 full-length CRF07_BC strains were elucidated using a bootscanning method.
  
  
  RESULTS
  Of 206 HIV-1-infected patients who received a diagnosis in 2004, 44.7% were infected with subtype B, 53.4% with CRF07_BC, and 1.5% with CRF01_AE. Ninety-eight percent (109/111) of IDUs were infected with CRF07_BC. Deletions of 7-11 amino acids in both p6(gag) and p6(pol) proteins were noted among the Taiwanese CRF07_BC strains. The CRF_07BC strains belonged to 2 phylogenetic clusters, and the first cluster contained only CRF07_BC strains from the southern part of Taiwan.
  
  
  CONCLUSIONS
  The Taiwanese CRF07_BC strains had 97% full-length sequence homology with the prototype from mainland China. CRF07_BC was first introduced into the southern region in 2002 and then spread to other regions in Taiwan in 2004.
authors.affiliation: AIDS Prevention and Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Yu-Ting
authors.initials: YT
authors.lastname: Lin
authors.forename: Yu-Ching
authors.initials: YC
authors.lastname: Lan
authors.forename: Yen-Ju
authors.initials: YJ
authors.lastname: Chen
authors.forename: Yu-Hui
authors.initials: YH
authors.lastname: Huang
authors.forename: Cheng-Ming
authors.initials: CM
authors.lastname: Lee
authors.forename: Tze-Tze
authors.initials: TT
authors.lastname: Liu
authors.forename: Wing-Wai
authors.initials: WW
authors.lastname: Wong
authors.forename: Jyh-Yuan
authors.initials: JY
authors.lastname: Yang
authors.forename: Chin-Tien
authors.initials: CT
authors.lastname: Wang
authors.forename: Yi-Ming Arthur
authors.initials: YM
authors.lastname: Chen
mesh_terms: D000595:Amino Acid Sequence; D004279:DNA, Viral / Q000032:analysis; D004196:Disease Outbreaks; D005260:Female; D015752:Genes, env / Q000235:genetics; D015750:Genes, gag / Q000235:genetics; D015751:Genes, pol / Q000235:genetics; D015658:HIV Infections / Q000453:epidemiology* / Q000209:etiology / Q000821:virology*; D015497:HIV-1 / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D015819:Substance Abuse, Intravenous; D011795:Surveys and Questionnaires; D013624:Taiwan / Q000453:epidemiology
chemical_list: D004279:DNA, Viral