江苏汉族人群p53第7内含子多态性与慢性萎缩性胃炎无相关性

No association between p53 gene intron 7 polymorphism and chronic atrophic gastritis in Han Chinese of Jiangsu province

目的：探讨江苏汉族人群p53第7内含子多态性与慢性萎缩性胃炎（CAG）之间的相关性．方法：提取80例CAG患者、76例健康体检人群基因组DNA，PCR特异性扩增p53基因第7，8外显子及其间的第7内含子，产物纯化后测序，将样品序列与标准序列进行比对，观察第7内含子多态性．组间的基因型及等位基因频率比较采用x^2检验．结果：CAG组P53基因第7内含子的第72位碱基和第92位碱基等位基因分别为T．G（32．5％）和C-T（67．5％），基因型表现为T-G／T-G（11．3％），C-T/T-G（42．5％1和C-T／C-T（46．3％）3种：在体检组中相应的等位基因T-G和C-T的频率是29．6％和70．4％，3种基因型频率分布分别为9．2％（T-G／T-G），40．8％（C-T／T-G）和50．0％（c．T／C．T）．等位基因频率和基因型分布在CAG组和体检组差异无统计学意义（P〉0．05）。T-G等位基因携带者和C-T等位基因携带者患CAG的危险性差异无统计学意义（OR=1．14）．结论：江苏汉族人群p53第7内含子多态性与CAG表遗传外显率无直接致病关系．

AIM： To explore whether the polymorphism of p53 gene intron 7 is associated with the occurrence of chronic atrophic gastritis （CAG） in Hart Chinese of Jiangsu province. METHODS： The genome DNA was extracted from tissues of 80 CAG patients and 76 healthy controls, and the exon 7 and 8 as well as the intron 7 within exon 7 and 8 of p53 gene were amplified by polymerase chain reaction （PCR）. The products were sequenced after purification. The polymorphism of p53 gene intron 7 was comparatively analyzed with the standard sequences. The genotypes and allelic frequencies compared between the two groups using chi-square test. RESULTS： In CAG cases, the allelic frequencies of the 72^th base pair （bp） and the 92^th bp in p53 gene intron 7 were 32.5% （T-G） and 67.5% （C-T）, and the frequencies of genotype T-G/T-G, C-T/T-G, and C-T/C-T were 11.3%, 42.5%, and 46.3%, respectively. Meanwhile in the controls, the allelic frequencies of T-G and C-T were 29.6% and 70.4%, and the frequencies of genotype T-G/T-G, C-T/T-G, and C-T/C-T were 9.2%, 40.8%, and 50.0%, respectively. There were no significant differences in the allelic frequencies and genotypic distributions between the two groups （P 〉 0.05）. The risk of CAG occurrence was not significantly different between the individuals with T-G and C-T allele （OR = 1.14）. CONCLUSION： There is no direct association between the polymorphism of p53 gene intron 7 and epigenetic penetrance of CAG in Han Chinese of Jiangsu province.