{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T05:52:54Z","timestamp":1775713974759,"version":"3.50.1"},"reference-count":34,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T00:00:00Z","timestamp":1775692800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Circulating recombinant forms (CRFs) play a critical role in the global transmission of HIV-1. In China, where CRF01_AE and CRF07_BC are the predominant circulating strains, second-generation recombinant viruses derived from these two CRFs are continually emerging. This study identified a novel CRF derived from CRF01_AE and CRF07_BC, designated CRF205_0107, and analyzed its genomic structure, parental lineages, and coreceptor usage.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      A dataset of HIV-1\n                      <jats:italic>pol<\/jats:italic>\n                      gene sequences was analyzed to screen for suspected unique recombinant clusters in Hangzhou, China. Plasma samples from HIV-1 infected individuals without known epidemiological linkages were selected for in-depth investigation. Near-full-length genomes (NFLGs) were generated using a two-segment amplification strategy. BLAST searches were conducted to detect highly homologous sequences. SimPlot software was used to analyze recombination patterns. Further validation was performed by constructing maximum-likelihood (ML) trees using IQ-TREE, while BEAST was employed to estimate the probable time of origin of the parental strains. Coreceptor tropism was predicted based on V3-loop sequences using the Geno2pheno algorithm.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Four HIV-1 NFLGs were obtained. BLAST analysis revealed that a previously reported NFLG sequence (Accession No. OP921950) from a man who has sex with men (MSM) individual in Hebei Province shared 98% similarity. Phylogenetic analysis demonstrated that these sequences formed a distinct monophyletic clade with 100% bootstrap support. Recombination analysis indicated that all five genomes shared a highly similar recombination pattern. Sub-regional phylogenetic analysis revealed that segments derived from CRF01_AE and CRF07_BC all clustered with the lineage associated with Chinese MSM (CRF01_AE_C4, CRF07_BC_N). Bayesian analysis estimated that CRF205_0107 originated around 2017\u20132018. Coreceptor tropism analysis based on the V3 loop indicated that all five NFLGs were CXCR4-tropic.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>The emergence of CRF205_0107 provides further evidence that second-generation HIV-1 recombinants involving CRF01_AE and CRF07_BC are frequently generated in China, reflecting an increasingly complex HIV-1 epidemic among MSM populations. This complexity may further drive the accelerated spread of HIV-1. These findings underscore the importance of strengthening the identification and molecular epidemiological surveillance of CRF01_AE\/CRF07_BC recombinant viruses, and highlight the urgency of curbing HIV-1 transmission among MSM in China.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fmicb.2026.1794333","type":"journal-article","created":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T05:20:45Z","timestamp":1775712045000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Molecular genetic characterization of a novel HIV-1 circulating recombinant form (CRF205_0107) among men who have sex with men in Hangzhou, China"],"prefix":"10.3389","volume":"17","author":[{"given":"Ling","family":"Ye","sequence":"first","affiliation":[{"name":"Department of HIV\/AIDS Control and Prevention, Hangzhou Center for Disease Control and Prevention (Hangzhou Health Supervision Institution)","place":["Hangzhou, China"]},{"name":"Zhejiang Key Laboratory of Multi-Omics in Infection and Immunity","place":["Hangzhou, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ke","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of HIV\/AIDS Control and Prevention, Hangzhou Center for Disease Control and Prevention (Hangzhou Health Supervision Institution)","place":["Hangzhou, China"]},{"name":"Zhejiang Key Laboratory of Multi-Omics in Infection and Immunity","place":["Hangzhou, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenjie","family":"Luo","sequence":"additional","affiliation":[{"name":"Department of HIV\/AIDS Control and Prevention, Hangzhou Center for Disease Control and Prevention (Hangzhou Health Supervision Institution)","place":["Hangzhou, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sisheng","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of HIV\/AIDS Control and Prevention, Hangzhou Center for Disease Control and Prevention (Hangzhou Health Supervision Institution)","place":["Hangzhou, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhou","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of HIV\/AIDS Control and Prevention, Hangzhou Center for Disease Control and Prevention (Hangzhou Health Supervision Institution)","place":["Hangzhou, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xingliang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of HIV\/AIDS Control and Prevention, Hangzhou Center for Disease Control and Prevention (Hangzhou Health Supervision Institution)","place":["Hangzhou, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiafeng","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of HIV\/AIDS Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention","place":["Hangzhou, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qin","family":"Fan","sequence":"additional","affiliation":[{"name":"Department of HIV\/AIDS Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention","place":["Hangzhou, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Min","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of HIV\/AIDS Control and Prevention, Hangzhou Center for Disease Control and Prevention (Hangzhou Health Supervision Institution)","place":["Hangzhou, China"]},{"name":"Zhejiang Key Laboratory of Multi-Omics in Infection and Immunity","place":["Hangzhou, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,9]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"106230","DOI":"10.1016\/j.jinf.2024.106230","article-title":"Identification of a complex second-generation HIV-1 circulating recombinant form (CRF158_0107) among men who have sex with men in China","volume":"89","author":"Chen","year":"2024","journal-title":"J. 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