静脉注射吸毒感染者体内HIV-1CRF07_BC的准种变异特征

Genetic Characteristics of Viral Quasispecies of HIV-1 CRF07_BC among Intravenous Drug Users

为了研究静脉注射吸毒者(IDU)体内HIV-1CRF07_BC病毒准种变异和遗传多样性特征,本文采用单基因组扩增(SGA)技术分别从6份CRF07_BC感染者血浆获得HIV-1病毒准种env基因gp120片段序列11～28条,采用构建系统进化树的方法进行聚类分析,描述感染者血浆中CRF07_BC病毒准种的变异特征;运用Simplot软件、分段系统进化树和对平均两两比对基因距离进行遗传多样性作图(Diversity plot)的方法分析病毒准种间的重组。系统进化树分析结果显示仅1个病例具有较高的遗传同质性,而其他5个病例的遗传异质性较高,主要表现为系统进化树上形成2～4个次级进化簇。此外,有3个病例存在病毒准种间的重组。本研究表明SGA技术能有效地分析感染者体内病毒准种复杂的变异特征。

To explore the genetic characteristics of viral quasispecies in HIV-1 CRF07_BC infections among intravenous drug users （IDU）, the gp120 fragments of HIV-1 env gene were amplified from plasma sam- ples collected from 6 CRF07_BC infected persons using single genome amplification and sequencing （SGA/ SGS） method, and 11 to 28 sequences were obtained from these samples, respectively. A neighbor-joining phylogenetic tree was reconstructed to describe the genetic characteristics of viral quasispecies. The Sire- plot, segments＇ phylogenetic trees and diversity plots based on average pairwise distance （APD） were used to identify the recombination events between quasispecies. The SGA sequences derived from single speci- men formed a large monophyletic cluster in the neighbor-joining phylogenetic tree and showed the complex topologic structures of viral quasispecies. Of the 6 CRF07_BC infected patients, only one possessed the high genetic homogeneity, whereas the other five individuals showed high heterogeneity, with two to four subclusters inside the monophyletic cluster for each specimen. In addition, the recombinant events were i- dentified among viral quasispecies from 3 cases. The results show SGA technique and phylogenetic analy- ses are useful tool to investigate the intrahost CRF07_BC gp120 complex quasispecies variation and high genetic diversity.