中国HIV-1 B'亚型毒株nef基因多态性及其对疾病进展影响的研究

目的 研究我国北方地区B'亚型HIV-1感染者病毒基因组中nef基因多态性、重要功能区的保守程度,探索其与疾病进展的关系.方法 HIV-1 B'亚型感染长期不进展者(LTNP)30例,典型进展者(TP)42例,从全血标本中提取全前病毒DNA,经nested-PCR扩增nef基因全长,扩增产物纯化后直接测序,对测得的序列进行系统进化和氨基酸变异分析,并计算比较LTNP组与TP的HIV/AIDS组氨基酸突变位置和频率的差异.结果 nef氨基酸序列长度可变区R21K/E/H/I/Q取代,TP组突变频率(59.52%)低于LTNP组(93.33%,P<0.005,OR=0.11).功能区外S15R/K/N取代,TP组突变频率(64.29%)高于LTNP组(33.33%,P<0.01,OR=3.60);K39R/E/N取代,TP组突变频率高于LTNP组(P<0.005).其他功能区内有少数序列发生变异,但在两组间无差异.结论 未发现中国北方地区HIV-1 B'亚型nef基因与疾病长期不进展相关联的明显缺失或缺陷,但nef基因序列长度可变区R21位K/E/H/I/Q取代R可能与疾病缓慢进展有关,S15R/K/N取代、K39R/E/N取代可能与疾病进展相关.nfe氨基酸序列的重要功能区较为保守.

Study on gene polymorphism of HIV-1 B' nef and its influence on disease progression in northern China

Objective To explore the polymorphism of nef gene and conservation level of functionally important domains of nef as well as their influences on HIV-1 disease progression of HIV-1 B'infected individuals in northern China.Methods 30 long term nonprogressors(LTNPs)and 42 typical progressors (TPs)were selected.Provirus DNA was extracted from whole blood sample.The full nef gene was amplified by nested-PCR.PCR product was sequenced directly after purification.Phylogenetic analysis and amino acid sequence mutation was applied on nef sequences to explore the differences between LTNPs and TPs.Results At position 15,the S15R/K/N substitution was detected.The frequency of TPs(64.29%)wsa higher than LTNPs(33.33%,P<0.01,0R=3.60);R21K/E/H/I.Q,TPs and LTNPs mutation frequency was 59.52%and 93.33%(P<0.005,OR=0.11);At position 39,K39R/E/N was only detected in TPs(23.81%,P<0.005).Conclusion No significant deletion or defect associated with disease progression wsa detected in nef gene of HIV-1 B'.But it suggested that K/E/H/I/Q mutation at 21 st amino acid of nef associated the disease nonprogression.R/K/N at 15 th amino acid of nef and R/E/N mutation at 39th amino acid of nef associated the disease progression in.HIV-1 B'.All domaias of nef amino acids sequences were comparatively conservative.