Characterization of a Novel HIV-1 Second-Generation Recombinant Form in Men Who Have Sex with Men in Beijing, China.

Cocirculation of multiple subtypes in the same population contributes significantly to the emergence of recombinant viruses. BJ2015EU19, a novel CCR5-tropic human immunodeficiency virus (HIV)-1, second-generation recombinant virus, was isolated from a man who has sex with men in Beijing, China. Phylogenetic analysis of the near full-length genome showed that BJ2015EU19 consisted of seven fragments from CRF01_AE and CRF07_BC. There were six recombinant breakpoints in the pol, vpu, env, and nef genes of BJ2015EU19, which were different from the other circulating recombinant forms and unique recombinant forms (URFs). The new emergence of the URF increases the complexity of the HIV epidemic in the Chinese homosexual group, and the ongoing generation of recombinant viruses may provide an important basis for future analysis of the recombination mechanism of HIV-1.