Near-Full-Length Genome Sequences of a Novel HIV-1 Circulating Recombinant Form, CRF01_AE/B′/C (CRF78_cpx), in Yunnan, China

We report a novel HIV circulating recombinant form (CRF78_cpx) composed mainly of CRF01_AE with inserts from subtypes B and C identified from three epidemiologically unlinked individuals in Yunnan province, China. Two of the subjects are heterosexual men and one is a male intravenous drug user. Sequencing and analyzing the near-full-length genome of these three isolates (YNTC88, YNTC19, and YNTC35) revealed identical recombination breakpoints in all three viruses, but considerable genetic diversity between them, across the genomes, indicating that this is not a newly created CRF, only newly detected. CRF78_cpx differs from previously documented CRF01-AE/B'/C forms in its distinct backbone, inserted fragment size, and breakpoints, and is not related to other described recombinants in the region such as CRF07_BC or CRF65_cpx (also composed of CRF01_AE, B', and C). Our present findings further enrich the diversity of the prevalent HIV-1 CRFs in Yunnan, which is considered as an epicenter of HIV-1 infections in China.