Dataset Information

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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Project description:BackgroundAn increase in non-B HIV-1 infections among men who have sex with men (MSM) in the United Kingdom (UK) has created opportunities for novel recombinants to arise and become established. We used molecular mapping to characterize the importance of such recombinants to the UK HIV epidemic, in order to gain insights into transmission dynamics that can inform control strategies.Methods and resultsA total of 55,556 pol (reverse transcriptase and protease) sequences in the UK HIV Drug Resistance Database were analyzed using Subtype Classification Using Evolutionary Algorithms (SCUEAL). Overall 72 patients shared the same A1/D recombination breakpoint in pol, comprising predominantly MSM but also heterosexuals and injecting drug users (IDUs). In six MSM, full-length single genome amplification of plasma HIV-1 RNA was performed in order to characterize the A1/D recombinant. Subtypes and recombination breakpoints were identified using sliding window and jumping profile hidden markov model approaches. Global maximum likelihood trees of gag, pol and env genes were drawn using FastTree version 2.1. Five of the six strains showed the same novel A1/D recombinant (8 breakpoints), which has been classified as CRF50_A1D. The sixth strain showed a complex CRF50_A1D/B/U structure. Divergence dates and phylogeographic inferences were determined using Bayesian Evolutionary Analysis using Sampling Trees (BEAST). This estimated that CRF50_A1D emerged in the UK around 1992 in MSM, with subsequent transmissions to heterosexuals and IDUs. Analysis of CRF50_A1D/B/U demonstrated that around the year 2000 CRF50_A1D underwent recombination with a subtype B strain.ConclusionsWe report the identification of CRF50_A1D, a novel circulating recombinant that emerged in UK MSM around 1992, with subsequent onward transmission to heterosexuals and IDUs, and more recent recombination with subtype B. These findings highlight the changing dynamics of HIV transmission in the UK and the converging of the two previously distinct MSM and heterosexual epidemics.

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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