Near Full-Length Genomic Characterization of Two Novel HIV Type 1 Second-generation Recombinant Form (CRF01_AE/CRF07_BC) from Guangxi, China.

CRF01_AE and CRF07_BC are the two predominant HIV-1 subtypes currently circulating in China. We identified here a novel CCR5-tropic HIV-1 second-generation recombinant form virus found in two individuals, (GX19017 and GX19032), which were isolated from two HIV-1 positive people in Guangxi, Southwest China. Phylogenic analyses indicated that these two sequences were all composed of two well-established circulating recombinant forms CRF07_BC and CRF01_AE, with four recombinant breakpoints observed in the pol, vpu/env and env gene regions, respectively. The recombinant CRF01_AE region was clustered with the previously described CRF01_AE sub-cluster 2 lineage, which was characterized by the susceptibility to phenotypic transfer. The genome structure is significantly different from other previously reported circulating recombinant forms (CRFs) and unique recombination forms (URFs). The emergence of a series of novel recombinant strains is indicative of the burgeoning complexity of the HIV-1 epidemic among the sexually transmitted population. Meanwhile, it may furnish significant insights into the dynamics and intricacy of the HIV-1 epidemic in China.