错配修复基因hMLH1突变Val384Asp在胃癌、食管癌发病中的作用

Etiological role of Val384Asp in hMLH1 gene in gastric and esophageal cancers

目的 :研究hMLH1基因错义突变Val384Asp在胃癌、食管癌发病中的作用。方法 :应用PCR SSCP和DNA测序技术 ,对 79例胃癌患者及其亲属、76例食管癌患者及其亲属、10 0例正常对照 ,进行了错配修复基因hMLH1错义突变Val384Asp筛选 ,确定其检出率。结果 :6 %的正常人携带hMLH1基因Val384Asp(杂合型 ) ;具有癌症家族史的胃癌患者及其亲属中Val384Asp的检出率与正常对照比较具有显著差异 (P <0 0 5 ;P <0 0 1)。以年龄分组比较 ,围绕中位发病年龄组的胃癌患者和低年龄的胃癌患者亲属组Val384Asp检出率较高 (P <0 0 5 )。食管癌患者及其亲属与正常对照之间无显著差异 (P >0 0 5 )。结论 :hMLH1基因Val384Asp等位基因频率在中国人中约为3% 。

Purpose:To study the etiological role of Val384Asp in hMLH1 gene in gastric and esophageal cancer.Methods:Genomic DNA were extracted from peripheral blood and were subjected to PCR SSCP and DNA sequencing to screen Val384Asp in hMLH1 gene in 79 gastric and 76 esophageal cancer patients, and in 79 and 76 first degree relatives of gastric and esophageal cancer patients respectively, and in 100 healthy persons. Results:There is a significant difference in the frequency of Val384Asp between gastric cancer patients with family history and healthy controls ( P <0 05). Significant differences also exist in the following comparisons:①the relatives of gastric cancer patients with family history to healthy controls ( P <0 01);②the gastric cancer patients whose ages are 45—64 years to healthy controls, and ③the relatives of gastric cancer patients who are younger than 45 years to healthy ( P <0.05). There is no significant difference between the esophageal carcinoma patients, the relatives of esophageal carcinoma patients and healthy controls ( P >0.05). Conclusions:The alleles frequency of Val384Asp in Chinese is 3%. It may partly play an etiological role in some of the stomach cancer patients.