中国汉族人CC趋化因子受体-5基因新的突变位点及多态性分析

目的：调查中国汉族人群人类免疫缺陷病毒－1协同受体CC趋化因子受体-5chemokine (CC)receptor 5,CCR5]编码区的基因多态性位点，为艾滋病的防治提供依据。方法：CCR5编码区用两对引物进行PCR扩增，设计测序引物依次测序，样本数为42份，用DNAstar分析测序结果，寻找单核苷酸多态性（single nucleotide polymorphism,SNP)位点。结果：在编码区共发现6个SNP位点，4个引起氨基酸改变：A184G、G503T、G668A、G999T；1个单碱基缺失，引起移码突变和提前终止。A184G、G503T、G999T3个中国汉族人所特有的SNP位点为首次发现，等位基因频率分别为1．2％，39．0％和9．5％；其中G503T分布明显不符合Hardy-Weinberg平衡。结论：中国汉族人CCR5编码区SNP位点有自己的特点，与高加索人和非洲人明显不同，与日本人也不完全一致。

Single nucleotide polymorphism loci of HIV-1 coreceptor CCR5 gene in Chinese Han people

OBJECTIVE: To investigate the single nucleotide polymorphism(SNP) loci of HIV-1 coreceptor CCR5 gene in Chinese Han people. METHODS: The coding region of CCR5 was amplified using 2 pairs of primers and the PCR products of all 42 healthy subjects were sequenced by 4 different primers. The results of sequencing were analyzed by DNAstar in search of SNP loci. RESULTS: Six SNP loci were discovered in the coding region of CCR5, among them four SNPs, i.e. 184A-->G, 503G-->T, 688G-->A and 999G-->T, cause amino acids changes and two SNPs are nonsense mutations. One cytosine deletion at the 894nt results in frame shift mutation and prematured termination. 184A-->G, 503G-->T and 999G-->T were found in Chinese Han people for the first time. The allelic frequencies of mutant 184G, 503T and 999T alleles were 1.1%, 21.1% and 10.0% in healthy Hans, respectively. The population distribution of G503T markedly deviated from Hardy-Weinberg equilibrium. CONCLUSION: The SNP loci in the coding region of CCR5 in Chinese Han people has its own characteristics, which is not consistent with those of Japanese and obviously different from those of Caucasian and African.