Molecular characterization of HIV-1 infection among men who have sex with men in Huai'an

Objective To gain more insights into genotype and evolutionary characteristics of HIV-1 infection among men who have sex with men (MSM) in Huai'an,Jiangsu. Methods Local confirmed cases in Huai'an were collected. HIV-1 env genes were amplified by nested reverse transcription polymerase chain reaction (RT-PCR)from (RNA) DNA, followed by sequencing and molecular evolutionary analysis. Results The distribution of HIV-1 infection genotypes among MSM were as follows:CRF01-AE(68.21%, 118/173),CRF07-BC(16.76%, 29/173),CRF08-BC(0.58%, 1/173),CRF55-01B(1.16%, 2/173) and B (13.29%, 23/173). Comparison of env gene sequences indicated that the HIV-1 strains circulating in Huai'an had high nucleotide identity with strains in Yunnan, Liaoning, Guangxi, Jiangsu and Hunan and clustering with their subtypes together on the phylogenetic tree. Overall, 58 haplotypes of CRF01-AE genotype were defined among individuals and CRF01-AE genotype of Huai'an isolates were equipped with a high haplotypic diversity index (0.999) and low nucleotide diversity index (0.150) also indicated the high genetic diversities. Conclusions HIV-1 genotypes are diverse in Huai'an. CRF55-01B was firstly detected among MSM in Huai'an. CRF01-AE is the dominant epidemic sub-type in MSM.