中文摘要：

目的 比较HIV-1 CRF01_AE、CRF07_BC和CRF08_BC毒株发生蛋白酶抑制剂（PI）、核苷类反转录酶抑制剂（NRTI）和非核苷类反转录酶抑制剂（NNRTI）主要耐药性突变的基因屏障,分析不同亚型耐药模式的差异.方法 纳入在广西壮族自治区南宁、柳州两市未经治疗的HIV感染者190例,采集外周静脉血,从血浆中提取HIV-1 RNA,扩增pol区并测序,用系统进化树分析序列的亚型,统计各序列每个主要突变位点由野生型密码子突变为耐药密码子所需的碱基转换和颠换的数量,根据转换与颠换发生概率约2.5：1的规律,将每个转换赋值设为1,每个颠换赋值设为2.5,计算各突变赋值之和,即为基因屏障值,采用Kruskal-Wallis检验法和Nemenyi法比较不同亚型的基因屏障差异.结果 共获得CRF01_AE、CRF07_BC和CRF08_BC毒株123株.CRF08_BC发生T/S69D的基因屏障低于CRF01_AE和CRF07_BC（χ2=107.501,P＜0.01）,CRF01_AE和CRF07_BC发生V118I和L210W的基因屏障低于CRF08_BC,CRF07_BC发生V106M的基因屏障低于CRF01_AE和CRF08_BC.结论 在相同的选择压力下,CRF01_AE和CRF07_BC比CRF08_BC易发生V118I和L210W,CRF08_BC比CRF01_AE和CRF07_BC易发生T/S69D,CRF07_BC比CRF08_BC和CRF01_AE易发生V106M.

英文摘要：

Objective To compare the genetic barriers to development of primary mutations related to drug resistance to protease inhibitors （PI）, nucleioside reverse transcriptase inhibitors （ NRTI ）, and non-nucleioside reverse transcriptase inhibitors （ NNRTI ） among human immunodeficiency virus （HIV）-1 CRF01_AE, CRF07_BC, and CRF08_BC strains, and to understand the difference of varying patterns of drug resistance related mutations within these subtypes. Methods One hundred and ninety naive HIV-positive subjects from Nanning City and Liuzhou City, Guangxi Zhuang Autonomous Region, were recruited. Peripheral blood samples were collected from all participants. HIV-1 RNAs were extracted from plasma, and the pol regions were amplified and sequenced. Sequences were subjected to phylogenetic analysis to determine the subtypes of HIV-1 isolates. Nucleotide transitions and transversions were counted for each primary mutation in these sequences. According to the phenomena that transitions occur on average 2. 5 times frequently than transversions, each transition was scored as 1, and each transversion scored as 2. 5. The sum of the scores for a particular substitution was calculated, and this value was taken as the genetic barrier to development of this mutation. Then, the differences of genetic barriers among the subtypes were assessed by Kruskal-Wallis test and Nemenyi test. Results A total of 123 sequences of CRF01_AE,CRF07_BC and CRF08_BC strains were selected. CRF08_BC had a lower genetic barrier for T/S69Dsubstitution than CRF01_AE and CRF07_BC （χ2 =107. 501, P〈0.01）, while CRF01_AE and CRF07_BC had lower genetic barriers for V118I and L210W substitution than CRF08_BC. In addition,CRF07_BC had a decreased genetic barrier for V106M compared with CRF01_AE and CRF08_BC.Conclusions In the presence of the same selective pressure, subtypes CRF01_AE and CRF07_BC may be more likely to develop V118I and L210W substitution than CRF08_BC. However, CRF08_BC may be more likely to develop T/S69D substitution than CRF