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目的研究辽宁省人类免疫缺陷病毒/艾滋病(HIV/AIDS)患者 gag-pol 区的基因序列特征。方法采集辽宁省99例 HIV-1感染者外周静脉血,提取前病毒 DNA,经巢式 PCR 方法扩增gag-pol 区2.6 kb 片段,与 HIV S 序列数据库中亚型参考序列共同构建系统进化树以区分亚型,并计算 gag-pol 区不同编码区域的基因离散率和 Ks/Ka 比值。结果在辽宁省99例 HIV-1感染者中发现A、B′、B、C、G 5种亚型,循环重组型 CRF01_AE、CRF03_AB、CRF06_cpx、CRF07_BC、CRF08_BC 5种循环重组型和循环重组型间的重组 ICR07/08。以 B′亚型最多见,其次为 CRF01_AE。在 gag-pol 区内,p17区、p2-p6区基因离散率高于 p24区、蛋白酶及逆转录酶编码区。但 B 亚型 p24区基因离散率处于较高水平。CRF07_BC 和 CRF08_BC 在 gag-pol 各区基因离散率及同义替换、错义替换普遍处于较低水平。各亚型毒株的 p2-p6区的 Ks/Ka 值最低,其均值<1,而 CRF01_AE 毒株 RT 区的 Ks/Ka 值高达10.45。结论辽宁省流行的 HIV-1 gag-pol 区亚型十分复杂。p24、蛋白酶及逆转录酶编码区是更为保守的区域。B 亚型毒株的 p24区承受较大的正向选择压力,CRF01_AE 毒株 RT 区承受了较大的负向选择压力。CRF07_BC 和 CRF08_BC 传入辽宁省的时间较短,奠基者效应明显。
Objective To study the gene sequence of gag-pol region in human immunodeficiency virus / HIV in Liaoning Province. Methods Peripheral venous blood was collected from 99 HIV-1 infected patients in Liaoning province. The prokaryotic DNA was extracted and the 2.6 kb fragment of gag-pol was amplified by nested PCR. The phylogenetic tree was constructed with the reference sequence of HIV S sequence database To distinguish subtypes and to calculate the genetic divergence rate and Ks / Ka ratio in different coding regions of the gag-pol region. Results Five subtypes of A, B ’, B, C and G were found in 99 cases of HIV-1 infected persons in Liaoning Province. Among the five types of circulating recombinant and circulating recombinant CRF01_AE, CRF03_AB, CRF06_cpx, CRF07_BC and CRF08_BC, Recombinant ICR07 / 08. The most common is B ’subtype, followed by CRF01_AE. In the gag-pol region, the gene divergence rate in p17 and p2-p6 regions was higher than that in p24 region, protease and reverse transcriptase coding region. However, the gene divergence rate of p24 gene in subtype B was at a high level. The genetic divergence rate and synonymous substitution of CRF07_BC and CRF08_BC in gag-pol regions were generally lower at the same time. The Ks / Ka values of the p2-p6 region of each subtype strain were the lowest, <1, while the Ks / Ka values of the CR region of the CRF01_AE strain were as high as 10.45. Conclusion The prevalence of HIV-1 gag-pol subtype in Liaoning province is very complicated. The p24, protease and reverse transcriptase coding regions are more conserved regions. The p24 region of subtype B strains underwent a greater positive selection pressure, and the RT region of CRF01_AE strains underwent a greater negative selection pressure. The time when CRF07_BC and CRF08_BC were introduced into Liaoning Province was relatively short, and the founders’ effect was obvious.