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

ABSTRACT: 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.

SUBMITTER: Wang W

PROVIDER: S-EPMC2928032 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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

Wang Wanhai W Jiang Shulin S Li Shenwei S Yang Kai K Ma Liying L Zhang Fengmin F Zhang Xiaoyan X Shao Yiming Y

AIDS research and human retroviruses 20081001 10

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 cir ...[more]

PMID: 18834324

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Dataset Information

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

Publications

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

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