Characterization of a Novel HIV-1 CRF01_AE/CRF07_BC Recombinant Virus Form in Guizhou, China

Identification of the Near Full-length Genome of a Novel HIV-1 CRF01_AE/CRF07_BC Recombinant with a Complex Genomic Structure Isolated in Hebei Province, China

BACKGROUND

During HIV genotypic drug resistance testing of patient samples in Baoding, Hebei Province, China, in 2022, a recombinant fragment was detected in the pol region of an HIV-1 strain.

OBJECTIVE

The objective of the study was to analyze the near full-length genome of a novel HIV-1 CRF01_AE/CRF07_BC recombinant with a complex genomic structure.

METHODS

Viral RNA was extracted from the blood of the infected individual and reverse transcribed to cDNA. Two overlapping segments of the HIV-1 genome were amplified using a nearendpoint dilution method and sequenced. Recombinant breakpoints were determined using RIP, jpHMM, and SimPlot 3.5.1 software. MEGA 6.0 software was used to construct a neighbor-joining phylogenetic tree.

RESULTS

We obtained the near full-length genome sequence (8680 bp) of a novel HIV-1 CRF01_AE/CRF07_BC recombinant. Recombination analysis showed that the genome comprised at least 12 overlapping segments, including six CRF07_BC and six CRF01_AE segments, with CRF07_BC as the backbone. The emergence of CRF01_AE/CRF07_BC recombinant strains indicated that HIV-1 co-infection is common. However, the increasing genetic complexity of the HIV-1 epidemic in China warrants continued investigation.

CONCLUSION

The increase in CRF01_AE/CRF07_BC recombinant viruses suggests that HIV-1 has a high genetic mutation rate in Hebei, China. This highlights the need for close monitoring of HIV-1 molecular epidemiologic changes to provide accurate, up-to-date information for effective disease control.

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.

Genomic Characterization of a Novel HIV-1 CRF01_AE/07_BC Recombinant Virus from a Married Man Who Has Sex with Men in Tianjin, China

We report in this study a novel HIV-1 second-generation recombinant form (TJIH0172) composed of CRF01_AE and CRF07_BC isolated from a married HIV-positive male subject infected through homosexual behavior in Tianjin, China. The phylogenetic analysis of the near full-length genome of TJIH0172 reveals that one region of CRF07_BC inserted into the CRF01_AE backbone with two recombinant breakpoints observed in the vpu and env gene regions, respectively. The CRF01_AE regions (the regions I and III) of the recombinant are greatly clustered with the CRF01_AE subcluster 4 lineage, which is mainly circulating among men who have sex with men (MSM) in northern China. The CRF07_BC region (II) is clustered with two sequences (JX960600 and KF250366), which were discovered in the MSM population in Liaoning Province and Beijing city in northern China, respectively. The emergence of the novel recombinant strain from a married man who has sex with men in Tianjin, China, highlights the increasing complexity of the HIV-1 epidemic between MSM and their female partners and further molecular epidemiological investigation should be taken to track married MSM and their female partners to prevent HIV transmit from HIV high-risk populations to general populations.

Genomic Characterization of a New HIV-1 CRF01_AE/CRF07_BC Recombinant Virus Form in Guizhou in Southwest China

A novel HIV-1 second-generation recombinant form (CRF01_AE/CRF07_BC) was isolated from an HIV-positive subject among men who have sex with men (MSM) in Guizhou province in Southwest China. Recombinant analyses of the near full-length genome suggested that the strain was composed of CRF01_AE and CRF07_BC with one region of CRF07-BC inserted into a CRF01-AE backbone. Further analysis indicated that the CRF01_AE regions of the recombinant were highly clustered together with a subcluster 4 lineage of CRF01_AE, which is exclusively circulating among MSM in China. The CRF07_BC region of the recombinant was clustered with the CRF07_BC cluster, which was identified among MSM. The emergence of the novel HIV-1 recombinant may be a harbinger of more novel intersubtypes recombinants occurring in Guizhou province in Southwest China, and was of great important in understanding the dynamics and complexity of the HIV-1 epidemic in this region.