title: Phylodynamic profile of HIV-1 subtype B, CRF01_AE and the recently emerging CRF51_01B among men who have sex with men (MSM) in Singapore.
abstract: HIV-1 subtype B and CRF01_AE are the predominant infecting subtypes among men who have sex with men (MSM) in Singapore. The genetic history, population dynamics and pattern of transmission networks of these genotypes remain largely unknown. We delineated the phylodynamic profiles of HIV-1 subtype B, CRF01_AE and the recently characterized CRF51_01B strains circulating among the MSM population in Singapore. A total of 105 (49.5%) newly-diagnosed treatment-naïve MSM were recruited between February 2008 and August 2009. Phylogenetic reconstructions of the protease gene (HXB2: 2239 - 2629), gp120 (HXB2: 6942 - 7577) and gp41 (HXB2: 7803 - 8276) of the env gene uncovered five monophyletic transmission networks (two each within subtype B and CRF01_AE and one within CRF51_01B lineages) of different sizes (involving 3 - 23 MSM subjects, supported by posterior probability measure of 1.0). Bayesian coalescent analysis estimated that the emergence and dissemination of multiple sub-epidemic networks occurred between 1995 and 2005, driven largely by subtype B and later followed by CRF01_AE. Exponential increase in effective population size for both subtype B and CRF01_AE occurred between 2002 to 2007 and 2005 to 2007, respectively. Genealogical estimates suggested that the novel CRF51_01B lineages were probably generated through series of recombination events involving CRF01_AE and multiple subtype B ancestors. Our study provides the first insight on the phylodynamic profiles of HIV-1 subtype B, CRF01_AE and CRF51_01B viral strains circulating among MSM in Singapore.
authors: Centre of Excellence for Research in AIDS (CERiA), Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors: Kim Tien
authors: KT
authors: Ng
authors: Kah Ying
authors: KY
authors: Ng
authors: Wei Xin
authors: WX
authors: Khong
authors: Kuan Kiat
authors: KK
authors: Chew
authors: Palvinder Kaur
authors: PK
authors: Singh
authors: Joe Kwan
authors: JK
authors: Yap
authors: Mei Ting
authors: MT
authors: Tan
authors: Yee Sin
authors: YS
authors: Leo
authors: Oliver
authors: O
authors: Laeyendecker
authors: Thomas C
authors: TC
authors: Quinn
authors: Adeeba
authors: A
authors: Kamarulzaman
authors: Kok Keng
authors: KK
authors: Tee
authors: Oon Tek
authors: OT
authors: Ng
mesh_terms: D015658:HIV Infections / Q000453:epidemiology / Q000235:genetics*; D015497:HIV-1 / Q000235:genetics*; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D010802:Phylogeny; D012846:Singapore / Q000453:epidemiology; D054299:env Gene Products, Human Immunodeficiency Virus / Q000235:genetics*
chemical_list: D054299:env Gene Products, Human Immunodeficiency Virus