广西壮族自治区2008—2009年HIV-1流行毒株基因型及其分布

Distribution of HIV-1 subtypes in Guangxi Zhuaug Autonomous Region, 2008-2009

目的了解广西地区目前HIV-1流行毒株的基因型及其分布。方法收集广西地区13个市294名2008--2009年新诊断的HIV感染者血浆标本和背景信息，感染途径主要为异性性传播（86．1％）。采用RT-PCR法分别扩增HIV-1gag．100i全长基因（分别为1584bp和3147bp）及enV基因的C2V3片段（558bp），序列编辑后用Genotyping及Mega5．03工具确定病毒的基因型，用Simplot和RecombinantHIV-1DrawingTool软件进行病毒基冈的重组分析。结果获得全长gag基因序列270条、全长poZ基因序列246条、eltv基因C2V3区序列22：3条，确定272例标本的基因型。CRF01AE占的比例最高（77．6％），其次为CRF08BC（10．7％）和CRF07BC（7．4％），有4例B（B’）亚型、1例G亚型，还有7例未知重组型。性别、民族间病毒基因型分布的差异无统计学意义。7株新型重组毒株有6株以CRF01AE为母株，嵌入B和／（或）c的片段，还有1株为CRF07BC和CRF08BC的二代重组。结论广西地区目前流行的HIV-1毒株以CRF01AE为主，并出现以CRF01-AE为母株嵌入其他毒株基因片段的新型重组毒株，呈现基因组结构复杂化趋势。

Objective To understand the distribution of HIV-1 subtypes in Guangxi Zhuang Autonomous Region. Methods 294 participants who were infected by HIV-1 in 2008-2009 and residing in 13 cities in Guangxi were enrolled into this study. Epidemiological information showed that heterosexual transmission was the main transmitting route. 1584 bp full length gag gene, 3147 bp full length pol gene and 558 bp env （C2V3） fragments were amplified by using RT-PCR and then directly sequenced. NCBI genotyping tool and Mega 5.03 software were used to determine the HIV subtypes. Simplot and Recombinant HIV-1 Drawing Tool were used for the analysis of recombination. Results A total of 739 sequences, including 270 gag, 246 pol and 223 env （C2V3）, were successfully obtained from 294 plasma specimens. Genotypes of HIV from 272 participants were determined. CRF01 AE was found the dominant （77.6%）, followed by CRF08_BC （ 10.7% ） and CRF07 BC （7.4%）. 7 unique recombinant forms, 4 subtype B （B＇） and 1 subtype G were also identified. No significant difference on the distribution of subtypes among different regions and ethnics was found. Among the 7 unknown recombinant forms, 6 strains were mosaic B and/or C fragments with CRF01_AE genome as the backbone, while one strain originated from CRF07 BC and CRF08_BC. Conclusion Currently, CRF01_AE was found the major subtype of HIV epidemic in Guangxi. New recombinant forms with CRF01_ AE as backbones had been emerging, which called for serious attention.