Identification of subtype B, multiple circulating recombinant forms and unique recombinants of HIV type 1 in an MSM cohort in China

• Published in: AIDS research and human retroviruses Vol. 24; no. 10; p. 1245
• Main Authors: Wang, Wanhai, Jiang, Shulin, Li, Shenwei, Yang, Kai, Ma, Liying, Zhang, Fengmin, Zhang, Xiaoyan, Shao, Yiming
• Format: Journal Article
• Language: English
• Published: United States 01.10.2008
• Subjects: Adult; China - epidemiology; Cluster Analysis; Cohort Studies; Genotype; HIV Infections - epidemiology; HIV Infections - virology; HIV-1 - classification; HIV-1 - genetics; HIV-1 - isolation & purification; Homosexuality, Male; Humans; Male; Middle Aged; Molecular Epidemiology; Molecular Sequence Data; Phylogeny; Polymorphism, Genetic; Recombination, Genetic; RNA, Viral - genetics; Sequence Analysis, DNA; Sequence Homology; China
• ISSN: 1931-8405
• DOI: 10.1089/aid.2008.0095

To study HIV-1 genetic diversity among HIV-positive men who have sex with men (MSM) in China, a cohort consisting of HIV-positive MSM was established in 2005 and was monitored every 2 years. In 2007, 44 HIVpositiveMSM subjects were genotyped, and the results showed HIV-1 subtype B decreased from 77.5% to41.9%, but non-B subtypes increased rapidly represented by CRF01_AE from 3.7% to 30.2% compared to 2005.In addition, one case of CRF07_BC was first identified in this population, which mainly circulated among HIV-1-infected injection drug users (IDUs) in China. There were 11 unique recombinant forms (URFs) consisting ofa recombination of CRF01_AE with subtype B or CRF07_BC. The subtype-specific phylogenic tree analysis showed that the genetic distance within subtype B group viruses was larger than the genetic distance within the CRF01_AE group (p 0.001). Of the identified viruses in the Chinese MSM population, over 80% of subtype B viruses might originate from the United States and Brazil, and over 85% of the CRF01_AE viruses mightoriginate from Thailand. In addition, epidemic study data showed that some of the HIV-1-infected MSM had foreign sexual partners (13.6%) and heterosexual activities (43.2%). The patients infected with HIV-1 URF viruses had more heterosexual encounters (54.5%) and more sexual partners (72.7%) compared to those infected with subtype B (44.4%; 33.3%) and CRF01_AE (23.1%; 69.2%) viruses. Taken together, we suspected that the genetic complexity of HIV-1 viruses identified in Chinese MSM populations was more likely a result of multiple introductions of viruses from the general population infected with HIV-1 through IDUs or heterosexual transmission.