脱嘌呤/嘧啶核酸内切酶基因氧化还原功能区单核苷酸多态性在散发性大肠癌中存在意义的探讨

Study on significance of single nucleotide polymorphisms in the redox domain of aprimidinic/apurinic endonuclease/redox factor-1 gene in Chinese sporadic colorectal cancer

目的 探讨脱嘌呤 /嘧啶核酸内切酶 (aprimidinic/ apurinic endonuclease/ redox factor- 1,APEX)基因氧化还原功能区单核苷酸多态性与散发性大肠癌的关系。方法 采用变性梯度凝胶电泳筛选、DNA测序的方法检测 15 0例散发性大肠癌和 14 3名健康人外周血 APEX基因氧化还原功能区的基因突变或基因多态性。结果 在散发性大肠癌 APEX基因氧化还原功能区中共检出 2个多态性位点 ,分别为 4 5 3G→T和 12 4 7A→ G。4 5 3T和 12 4 7G的基因频率分别为 1.3%和 5 .7% ;对照人群中上述两位点的基因频率分别为 1.0 5 %和 4 .5 5 % ,其基因型分布符合 Hardy- Weinberg平衡定律。散发性大肠癌和健康人群中两位点的基因频率差异无显著性。结论 APEX基因氧化还原功能区的基因多态性与散发性大肠癌的发生无关。该区多态性分布具有较明显的种族差异。

ObjectiveTo investigate the relationship between the single nucleotide polymorphisms(SNPs) in the redox domain of aprimidinic/apurinic endonuclease/redox factor-1( APEX ) gene and the development of sporadic colorectal cancer.MethodsOne hundred and fifty cases of sporadic colorectal cancers and 143 peripheral blood samples from healthy population were screened for genetic polymorphisms or mutations in the redox domain by denaturing gradient gel electrophoresis followed by DNA sequencing. ResultsThere were two SNPs identified in the redox domain of APEX gene, namely, 453G→T and 1247A→G.The gene frequencies of 453T and 1247G were 1.3% and 5.7%, respectively, in patient group, while 1.05% and 4.55%, respectively, in healthy population. The genotype distribution at the two sites in healthy population was consistent with Hardy-Weinberg equilibrium. There was no difference in gene frequencies at the two sites between cancer patients and healthy population. Conclusion The polymorphisms in the redox domain of APEX gene are irrelevant to the development of sporadic colorectal cancer, but their distribution may vary greatly among tribes.