【作者】 麦志丹；

【导师】 梁浩；

【作者基本信息】 广西医科大学 ， 流行病学与卫生统计学， 2007， 硕士

【摘要】 目的调查HIV-1感染相关的CCR5△32、CCR2-64I及SDF1-3’A在广西壮、汉族人群中的等位基因频率及基因多态性的分布。通过课题的研究,将揭示它们在广西壮、汉族健康人群和HIV-1感染者中的等位基因突变频率及其多态性特点。了解广西壮、汉族人群对HIV-1的遗传易感性,为广西HIV-1的流行特点、致病机理等方面提供基础资料。方法在广西天等县、横县和南宁市通过随机抽取方法收集壮、汉族健康人群共180例(其中壮族120例,汉族60例)以及壮、汉族HIV-1感染者共60例(其中壮、汉族各30例)作为研究对象。所有的研究对象提取染色体基因组DNA,经过PCR(聚合酶链式反应)扩增不同的基因特定片段和PCR-RFLP(PCR-限制性片段长度多态性)检测其突变,分析HIV-1感染相关的基因多态性,并将研究结果与国内外报道的其他民族结果进行比较。结果(1)CCR5:120例壮族健康人群检测,CCR5△32(CCR5等位基因编码区域第185号氨基酸密码子以后发生了32个碱基缺失的突变)未发现有突变,等位基因频率为0。30例壮族HIV-1感染者中,CCR5△32未发现有突变,等位基因频率为0。60例汉族健康人群中,CCR5△32未发现有突变,等位基因频率为0。30例汉族HIV-1感染者中,CCR5△32未发现有突变,等位基因频率为0。(2)CCR2:120例壮族健康人群检测,CCR2-64I(CCR2基因的读码框架起始点ATG后的第190位点G→A核苷酸的替换)纯合突变0例,占总数的0;杂合突变61例,占总数的50.83%。等位基因频率为25.42%。30例壮族HIV-1感染人群检测,CCR2-64I纯合突变0例,占总数的0;杂合突变12例,占总数的40%。等位基因频率为20%。60例汉族健康人群检测,CCR2-64I纯合突变0例,占总数0;杂合突变31例,占总数的51.67%。等位基因频率为25.83%。30例汉族HIV-1感染人群检测,CCR2-64I纯合突变0例,占总数的0;杂合突变14例,占总数的46.67%。等位基因频率为23.33%。(3)SDF1:120例壮族健康人群检测,SDF1-3’A(是编码基因801位的G突变为A,位于3’端非翻译区)纯合突变12例,占总数的10%;杂合突变42例,占总数的35%。等位基因频率为27.50%。30例壮族HIV-1感染人群检测,SDF1-3’A纯合突变2例,占总数的6.67%;杂合突变14例,占总数的46.67%。等位基因频率为30%。60例汉族健康人群检测,SDF1-3’A纯合突变4例,占总数的6.70%;杂合突变25例,占总数的41.67%。等位基因频率为27.50%。30例汉族HIV-1感染人群检测,SDF1-3’A纯合突变4例,占总数的13.33%;杂合突变11例,占总数的36.67%。等位基因频率为31.17%。结论(1)本研究中广西壮、汉族人群未检测到CCR5△32突变。说明广西壮、汉族人群对HIV-1的感染在辅助受体CCR5上具有较低的遗传保护性,对巨噬细胞嗜性HIV-1的易感性高于欧美白人。(2)广西壮、汉族人群CCR2辅助受体的基因突变率高于欧美白人。广西壮、汉族间的基因突变率差别没有显著意义。(3)SDF1-3’A基因在广西壮、汉族人群中均有突变,但两组人群之间的基因突变率差别没有显著性。广西壮族基因变异率高于欧美白人。更多还原

【Abstract】 PURPOSE Very little is known about allele frequency and polymorphism related to human immunodeficiency virus type 1 (HIV-1), SDF1, CCR2, and CCR5 among indigenous Zhuang,Han population, and HIV-1 infected people in Guangxi. This study was designed to investigate the allele frequency and the characteristics of gene polymorphism of CCR5Δ32, CCR2-64I, and SDF1 -3 ’A in these population . In this study we also attempted to evaluate the groups hereditary susceptibility to HIV-1 infection and HIV-1 epidemic feature which was implicated in these genes mutation in Guangxi.METHODS The full length fragment of CCR5 gene coding region was amplified by PCR amplification and sequenced in 180 healthy subjects and 60 HIV-1 infected individuals from Zhuang and Han ethnic group. And then the deletion allele was determined by electrophoresis and sequencing data were analyzed by using CLUSTAL X software for identification of polymorthism. Furthermore, the mutation of CCR2-64I and SDF1-3’A genes was examined by PCR-restriction fragment-length polymorthism-based(PCR-RFLP) assay in these subjects.RESULTS(1)CCR5:None of CCR5 A 32 (32 base deletion after nucleotide 185 )was found either in 120 Zhuang and 60 Han healthy subjects or in 30 HIV-1 infected individuals from Zhuang and Han population,respectively.The deletion allelic frequency of these subjects was 0.(2) CCR2:Of 120 Zhuang healthy subjects, none of CCR2-64I homozygous mutation (G to A at nucleotide 190) was found; 61 of subjects (50.83%) were CCR2-64I heterozygous mutation. The allelic frequency was 25.42%. Same result of CCR2-64I homozygous mutation was identified in 30 HIV-1 infected individuals from Zhuang population, while 12 of samples (40%) were CCR2-64I heterozygote . The allelic frequency accounted for 20%.In contrast,there had also none of CCR2-64I homozygous mutation among 60 healthy Han subjects; 31 of them (51.67%) were CCR2-64I heterozygote. This genetic allelic frequency was 25.83%. Of 30 HIV-1 infected Han population, none of CCR2-64I homozygote was demonstrated as well, while 14 of them (46.67%) were CCR2-64I heterozygous mutation. This genetic frequency accounted for 23.33%.(3)SDF1:Of 120 Zhuang healthy subjects, 12 of subjects(10%) were SDF1-3’A homozygous mutation (G to A at nucleotide 801) and 42 of subjects (35%) were SDF1-3’A heterozygous mutation. The allelic frequency was 27.50%. 2 subjects of SDF1-3’A homozygous mutation was identified in 30 HIV-1 infected individuals from Zhuang population, while 14 of samples (46.67%) were SDF1-3’A heterozygote .The allelic frequency accounted for 30%.In contrast, there had 4 samples (6.67%) of SDF1-3’A homozygous mutation among 60 healthy Han subjects; 25 of them (41.67%) were SDF1-3’A heterozygote. This genetic allelic frequency was 27.50%. Of 30 HIV-1 infected Han population, 4 (13.33%) of SDF1-3’A homozygote was determined as well, while 11 of them (36.67%) were SDF1-3’A heterozygous mutation. This allelic frequency accounted for 31.17%.CONCLUTION(1) There isn’t any CCR5Δ32 in Zhuang as well as in Han population. The results suggest that the resistant effect of CCR5Δ32 to infection with HIV-1 is lower in Zhuang and Han population, and the inherent susceptibility is higher in comparison with Europe.(2) The CCR2-64I frequency of Zhuang and Han population is higher than that of Europe. However, there is no difference between Zhuang population and Han population.(3) Compared with Europe, the SDF1-3’A frequency of Zhuang and Han population is higher, while there is no difference between Zhuang population and Han population.更多还原