We analyzed the near full-length genome (NFLG) of an HIV-1-positive sample(027A) with an undetermined subtype to determine the recombinant characteristics and possible source of the parental virus. 027A is a novel HIV-1 second-generation recombinant form composed of CRF01_AE and subtype B, detected from a married HIV-1-positive male subject who was infected through homosexual transmission in Baoding, Hebei province, China. The NFLG phylogenetic tree analysis suggested that the strain was close to circulation recombinant forms' (CRFs') reference sequences involved with CRF01_AE, but formed a distinct monophyletic cluster separately from them. This indicated that the strain might be a unique CRF01_AE-related recombinant from. Furthermore, the results of RIP and jpHMM further demonstrated that the NFLG sequence of the strain was composed of CRF01_AE and subtype B. The strain was two CRF01_AE fragments inserted into B backbone. Phylogenetic analysis illustrated that the CRF01_AE subregions were from the previously identified CRF01_AE cluster 4, and the B subregions were correlated with the B strains originated from Europe and America. They were all the lineages widely prevalent in men who have sex with men (MSM) population in China. In recent years, a large number of recombinant originated from CRF01_AE and B strains are constantly emerging in MSM population in China. This continual and recurrent recombination between CRF01_AE and B in high-risk group people deserves more attention and further monitoring.
Keywords: Baoding; CRF01_AE/B; HIV; MSM.