title: Genetic diversity and drug resistance among newly diagnosed and antiretroviral treatment-naive HIV-infected individuals in western Yunnan: a hot area of viral recombination in China.
abstract: BACKGROUND
  The emergence of an HIV-1 epidemic in China was first recognized in Dehong, western Yunnan. Due to its geographic location, Dehong contributed greatly in bridging HIV-1 epidemics in Southeast Asia and China through drug trafficking and injection drug use; and also extensively to the HIV genetic diversity in Yunnan and China. We attempt to monitor HIV-1 in this area by studying the HIV-1 genetic distribution and transmitted drug resistance (TDR) in various at-risk populations.
  
  
  METHODS
  Blood samples from a total of 320 newly HIV-1 diagnosed individuals, who were antiretroviral therapy (ART)-naive, were collected from January 2009 to December 2010 in 2 counties in Dehong. HIV-1 subtypes and pol gene drug resistance (DR) mutations were genotyped.
  
  
  RESULTS
  Among 299 pol sequences successfully genotyped (93.4%), subtype C accounted for 43.1% (n=129), unique recombinant forms (URFs) for 18.4% (n=55), CRF01_AE for 17.7% (n=54), B for 10.7% (n=32), CRF08_BC for 8.4% (n=25) and CRF07_BC for 1.7% (n=5). Subtype distribution in patients infected by different transmission routes varied. In contract to the previous finding of CRF01_AE predominance in 2002-2006, subtype C predominated in both injecting drug users (IDUs) and heterosexually transmitted populations in this study. Furthermore, we found a high level of BC, CRF01_AE/C and CRF01_AE/B/C recombinants suggesting the presence of active viral recombination in the area. TDR associated mutations were identified in 4.3% (n=13) individuals. A total of 1.3% of DR were related to protease inhibitors (PIs), including I85IV, M46I and L90M; 0.3% to nucleoside reverse transcriptase inhibitors (NRTIs), including M184I; and 2.7% to non-nucleoside reverse transcriptase inhibitors (NNRTIs), including K103N/S, Y181C, K101E and G190A.
  
  
  CONCLUSIONS
  Our work revealed diverse HIV-1 subtype distributions and intersubtype recombinations. We also identified a low but significant TDR mutation rate among ART-naive patients. These findings enhance our understanding of HIV-1 evolution and are valuable for the development and implementation of a comprehensive public health approach to HIV-1 DR prevention and treatment in the region.
authors.affiliation: Yunnan Center for AIDS/STD Control and Prevention, Yunnan Center for Disease Control and Prevention, Kunming, Yunnan 650022, China.
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Yanling
authors.initials: Y
authors.lastname: Ma
authors.forename: Song
authors.initials: S
authors.lastname: Duan
authors.forename: Hui
authors.initials: H
authors.lastname: Xing
authors.forename: Shitang
authors.initials: S
authors.lastname: Yao
authors.forename: Yingzhen
authors.initials: Y
authors.lastname: Su
authors.forename: Hongbing
authors.initials: H
authors.lastname: Luo
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.forename: Huichao
authors.initials: H
authors.lastname: Chen
authors.forename: Liru
authors.initials: L
authors.lastname: Fu
authors.forename: Aijuan
authors.initials: A
authors.lastname: Qu
authors.forename: Chin-Yih
authors.initials: CY
authors.lastname: Ou
authors.forename: Manhong
authors.initials: M
authors.lastname: Jia
authors.forename: Lin
authors.initials: L
authors.lastname: Lu
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use; D002681:China; D024882:Drug Resistance, Viral / Q000235:genetics*; D005260:Female; D015751:Genes, pol / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics; D005838:Genotype; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D019380:Anti-HIV Agents