广东省氡辐射地区人群hOGG1基因5'侧翼区遗传多态性分布

Genetic polymorphisms of hOGG1 in the 5'-flank region in population of radon exposure area in Guangdong Province

目的筛查广东省氡辐射地区汉族人群中8-羟基鸟嘌呤DNA糖苷酶(hOGG1)基因5'侧翼区遗传多态性位点,并分析其遗传分布特征。方法采用单纯随机抽样方法,选择60名广东氡辐射地区汉族人群作为研究对象,采集肘静脉血抽提其基因组DNA,采用聚合酶链式反应法扩增获得hOGG1基因5'侧翼区(-1721 nt^+164 nt)目的片段产物后纯化直接测序,筛查并确证潜在的单核苷酸多态性(SNP)位点,对SNP位点进行遗传特征分析,并与人类基因组单体型图(Hap Map)数据库中报道的不同人群分布数据进行比较。结果 PCR扩增和成功测序60名(120条染色体)氡辐射地区汉族人群hOGG1基因5'侧翼区目的片段。序列比对发现该人群中8个SNP位点;其中,3个已知位点-1493 G>A、-834 G>C和-18 G>T的最小等位基因频率分别为4.2%、0.8%和3.3%;5个新位点-1455 G>A、-1293 A>T、-1187 C>A、-337 C>A和-323 G>A的最小等位基因频率分别为0.8%、23.3%、7.5%、36.7%和0.8%。-1493 G>A的等位基因频率在氡辐射地区汉族人群的分布与Hap Map数据库中欧洲高加索人种/人群的分布比较,差异有统计学意义(P<0.05)。结论筛查出广东氡辐射地区汉族人群中hOGG1基因5'侧翼区共8个SNP位点,并获得其等位基因遗传分布特征,为后续目标人群多态性单体型构建及其功能分析提供基础。

Objective To screen genetic polymorphisms in the 5＇-flank region of 8-hydroxyguanine DNA glycosylase （hOGG1） gene and analyze the characteristics of their genetic distribution in Han population of radon exposure area in Guangdong Province. Methods A simple random sampling method was used to select 60 subjects as radon exposure population. The genomic DNA samples were extracted from peripheral blood. The single nucleotide at - 1721 nt- ＋ 164 nt locus of hOGG1 were screened using polymerase chain reaction （PCR） amplification, purification and direct sequencing for polymorphisms. Genetic characteristics of single nucleotide polymorphisms （SNP） in the study population were analyzed and compared with different populations reported in HapMap data. Results The 5＇-flank region of hOGG1 were amplified and sequenced in these 60 individuals （120 chromosomes） of healthy Han Chinese in radon exposure area. Eight SNPs were identified by sequence alignment in the study population. Among them, there was 3 known polymorphisms and their minor allele frequencies （MAF） were -1493 G〉A （4.2%）, -834 G〉C （0.8%） and -18 G〉T （3.3%）, respectively. The MAF of other 5 novel variations were - 1455 G 〉 A （0. 8% ）, - 1293A 〉 T （ 23.3% ） , - 1187 C 〉 A （7.5%）, - 337 C 〉 A （36. 7% ） and - 323 G 〉 A （0. 8% ）, respectively. The differences in the MAF distribution of - 1493 G 〉 A between the study population and the HapMap-CEU were statistically significant （ P 〈 0. 05 ）. Conclusion Eight SNPs and their genetic characteristics were screened and identified in the 5 ＇-flank region of hOGG1 of Han Chinese population in radon exposure area. This result provides a basis for construction of polymorpbism haplotypes and functional analysis for the target population.