Department of Science Research and Information Management, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China.
School of Public Health, Capital Medical University, Beijing, China.
AIDS Res Hum Retroviruses. 2021 Dec;37(12):936-945. doi: 10.1089/AID.2020.0255. Epub 2021 Aug 3.
The HIV-1 epidemic was mainly driven by men who have sex with men (MSM) recently in Beijing, China, with high genetic diversity. Novel recombinant strains were frequently reported at 3.4%-9.9%. It is imperative to interpret the recombinant modes and the putative transmission sources by near full-length genome (NFLG). Four individuals from the MSM population were identified as novel recombinant strains during surveillance of pretreatment drug resistance. NFLG sequences were harvested by near end-point dilution and nested PCR with two overlapping half fragments. Phylogenetic inference was performed with subtyping reference sequences and major parental strain sequences, to explore the patterns of genetic recombinant and potential sources of parent strains. The breakpoints were determined using SimPlot 3.5 to draw genome mosaic map, and the potential parental strains were confirmed by Mega 6.0 using segmental neighbor-joining trees. BL19487-00 and BL1948-00 sequences were obtained from epidemiologically linked individuals and shared similar breakpoints (HXB2 nt 4,497 ± 8 to 4,722) with substitution of subtype B gene segment in the backbone of CRF55_01B. BL3104-00 and BL4307-00 carried seven and eight breakpoints, respectively, in the backbone of CRF65_cpx with g5 CRF01_AE substitutions. The recombinant fragments were located around , , and genes, with and -3'- genes only for BL4307-00. No transmitted drug resistance was observed with the four unique recombinant forms (URFs), except for some drug resistance associated mutations. The advent of URFs around CRF55_01B and CRF65_cpx identified in recent years implied that the sexual behaviors were active and the epidemic of HIV was complicated among MSM in Beijing. Molecular epidemiological surveillance and precise control should be reinforced for this population.
近年来,中国北京的男男性行为人群(MSM)中的 HIV-1 疫情主要由该人群驱动,具有较高的遗传多样性。经常报道新型重组毒株,频率为 3.4%-9.9%。通过近全长基因组(NFLG)解释重组模式和可能的传播来源至关重要。在治疗前耐药性监测中,从 MSM 人群中发现了 4 例新型重组株。通过近终点稀释和嵌套 PCR 用两个重叠的半片段收获 NFLG 序列。使用亚分型参考序列和主要亲本株序列进行系统发育推断,以探索遗传重组模式和潜在亲本株来源。使用 SimPlot 3.5 确定断点,以绘制基因组嵌合图谱,并使用 Mega 6.0 通过分段邻接树确认潜在亲本株。BL19487-00 和 BL1948-00 序列分别从流行病学相关个体中获得,它们具有相似的断点(HXB2nt4497±8 至 4722),并在 CRF55_01B 主干中替代了 B 亚型基因片段。BL3104-00 和 BL4307-00 在 CRF65_cpx 的主干中分别有 7 个和 8 个断点,g5 CRF01_AE 取代。重组片段位于 、 、 和 基因周围,只有 BL4307-00 具有 和 -3'-基因。除了一些耐药相关突变外,这四种独特重组形式(URFs)均未观察到传播耐药性。近年来在 CRF55_01B 和 CRF65_cpx 周围发现的 URFs 的出现表明,北京 MSM 中的性行为活跃,HIV 流行复杂。应加强对此人群的分子流行病学监测和精准控制。