Characterization of Three Novel HIV-1 Second-Generation Recombinants (CRF01_AE/CRF07_BC) Identified in Shenzhen, China.

The prevalence of recombinant forms has greatly enhanced HIV-1 genetic diversity. Under co-circulation of major epidemic HIV-1 strains (CRF01_AE and CRF07_BC) in China, more CRF01_AE and CRF07_BC as the backbone of HIV-1 second-generation recombinants (SGRs) are also emerging. In this study, we identified three similar novel HIV-1 SGR strains composed of CRF01_AE and CRF07_BC from HIV-1 positive individuals in Shenzhen, China. Near full-length genome phylogenetic and recombinant analysis confirmed that these unique recombination forms were CRF01_AE and CRF07_BC strains recombined. Further subregion phylogenetic analysis indicated that all CRF01_AE fragments were from CRF01_AE cluster 4 prevalent among men who have sex with men, and all subtype B and C fragments derived from CRF07_BC. The emergence of novel recombinants of CRF01_AE/CRF07_BC indicates the increased genetic diversity of the HIV epidemic in Shenzhen. It is necessary to monitor HIV-1 SGR strains among high-risk populations for the epidemic dynamics of HIV-1 in Shenzhen, China.