A Novel HIV-1 Second-Generation Recombinant Form (CRF01_AE/07_BC) Among Heterosexuals in Nei Monggoi Autonomous Region in China

Genomic characterization of a new CRF01_AE/CRF07_BC case from a MSM patient in Guangdong, China

The CRF01_AE and CRF07_BC clades dominate the human immunodeficiency virus (HIV) epidemics in China. Both clades have been identified in the men who have sex with men (MSM) population in Guangdong province, raising a serious concern of possible complex recombination events ahead. Here, we report the first case of CRF01_AE/CRF07_BC recombinant sampled from a MSM patient in southern China. The genomic structure of this case is a mosaic with some regions resembling the CRF01_AE and CRF07_BC clades. Our phylogenetic analyses show that the two parental lineages of this recombinant virus were mainly found in the MSM population. This case has a different genomic composition compared with other recombinants descended from the same parental clades CRF01_AE and CRF07_BC. Our finding suggests that the MSM populations have become a hotspot for expanding viral diversity through the viral recombination mechanism. Therefore, further epidemiologic surveillance and monitoring should be conducted within the MSM populations to help advance our knowledge of viral transmission mechanisms. Additionally, these measures will serve to enhance the control and prevention of HIV/acquired immunodeficiency syndrome in China.

A Novel Recombinant Form of HIV-1 CRF01_AE/CRF07_BC Identified by Near Full-Length Genome in Shaanxi, China

Recently multiple kinds of unique recombinant forms of HIV-1 CRF01_AE/CRF07_BC were identified in China. In this study, we report another near full-length genome of a novel recombinant form (SN121) between CRF01_AE and CRF07_BC from an HIV-1-infected male through heterosexual behavior in Shaanxi province, China. The analysis of SN121 showed that the genome composed of seven interlaced segments, including three CRF07_BC and four CRF01_AE segments with CRF01_AE as the backbone. Six breakpoints were observed in the pol and env gene regions, which are different from the previously identified CRF01_AE/07_BC recombinant forms in China. This novel emerging recombinant form suggested the complicated genetic diversity and the active local transmission of HIV-1 in Shaanxi province. Further monitoring should be performed to elucidate the possible molecular evolution of this novel recombinant form.

A Unique Second-Generation Recombinant Form of HIV-1 Identified Among Men Who Have Sex with Men Population in Beijing, China

In China, CRF01_AE and CRF07_BC are the most circulating strains of HIV-1, more and more second-generation recombinant forms have been isolated around the two strains. The same situation happened in Beijing in recent years. In our study, we have isolated a new second-generation recombinant form of HIV-1 from a male patient who was infected by homosexual behavior. Polygenetic analysis revealed that the sequence includes five CRF01_AE fragments and four CRF07_BC fragments. CRF01_AE is the skeleton of the recombinant which was inserted with four CRF07_BC fragments. The emergency of such second-generation recombinant forms manifests the diversity of the HIV-1 epidemic. Consequently, further investigation of molecular epidemiology is needed to track the genetic evolution of HIV-1.

Genome Sequence of a Novel HIV-1 Circulating Recombinant Form (CRF79_0107) Identified from Shanxi, China

We report a novel HIV-1 circulating recombinant form (CRF79_0107) from three epidemiologically unlinked patients through sexual contact in Shanxi province of China. This is the first second-generation circulating recombinant form identified in China. The breakpoint analysis of recombinants showed that CRF79_0107 was composed of CRF01_AE and CRF07_BC, with three CRF07_BC segments inserted into the CRF01_AE backbone. The emergence of CRF79_0107 increases the complexity of the HIV epidemic in China.

Near Full-Length Genomic Characterization of a Novel HIV-1 Unique Recombinant (CRF55_01B/CRF07_BC) from a Malaysian Immigrant Worker in Zhejiang, China

Recombinant forms contribute substantially to the genetic diversity of human immunodeficiency virus type 1 (HIV-1). Here we report a novel HIV-1 recombinant detected from a comprehensive HIV-1 molecular epidemiologic study among cross-border populations in China. Near full-length genome (NFLG) phylogenetic analysis showed that the novel HIV-1 recombinant ZJCIQ15005, which was isolated from a Malaysian immigrant worker in Zhejiang, China, clustered with CRF55_01B reference sequences but set up a distinct branch. Recombinant analysis showed that the NFLG of ZJCIQ15005 composed of CRF55_01B (as the backbone) and CRF07_BC, with 12 recombinant break points observed in the pol, vif, vpr, tat, rev, env, nef, and 3'LTR regions. This is the first detection of a novel HIV-1 recombinant (CRF55_01B/CRF07_BC) in immigrant workers in China. The emergence of this recombinant may increase the complexity of the HIV-1 epidemic in China and suggests the importance of continuous surveillance of the dynamic changes of HIV-1.

Near Full-Length Genome Identification of a Novel HIV-1 Recombinant Form (CRF01_AE/CRF07_BC) in Zhejiang, China

CRF01_AE and CRF07_BC are the two major circulating recombinant forms (CRFs) in China. Furthermore, many kinds of unique recombinant forms (URFs) between CRF01_AE and CRF07_BC were recently identified in China. Here we detected a novel recombinant of CRF07_BC/CRF01_AE, whose genome structure is distinctly different from other URFs reported before. The phylogenetic analysis of the near full-length sequence of 15zj032 reveals that three regions of CRF01_AE insert into the CRF07_BC backbone. Recently, the continued emergence of novel URFs implies that super infections of different subtypes of HIV-1 are common in China and should be given enough importance.