中文摘要：

目的：探讨中国华东汉族人群叶酸还原载体（reduced folate carrier，RFC1）基因G80A多态与胃癌易感性的关系。方法：本组为病例对照研究，经组织学确诊的宜兴高发区胃腺癌病例261例，并选择与病例年龄和性别频数匹配的人群对照295例，以PCR内切酶片段长度多态性方法，比较不同基因型与胃癌风险的关系，并探讨吸烟、饮酒等因素在其中的影响。结果：与携带80GG基因型者比较，携带80AA基因型者胃癌风险增加1．79倍（校正OR=2．79，95％CI：1．77～4．39）；以携带80GG和GA基因型者为参照（隐性模型），80AA变异基因型者胃癌风险增加1．59倍（校正OR=2．59，95％CI：1．77～3．80），且这一显著的相关性在60岁以上（校正OR=2．96，95％CI：1．63～5．37）、女性（校正OR=8．28，95％CI：2．95～23．26）、非吸烟者（校正OR=3．68，95％CI：1．94～6．98）和非饮酒者（校正OR=3．08，95％CI：1．76～5．41）中更为显著。结论：RFC1G80A多态可能与中国汉族人群胃癌遗传易感性有关，值得进一步进行功能学探讨及大样本人群验证。

英文摘要：

Objective：To investigate the relationship between polymorphism of reduced folate carrier gene RFC1-G 80A G 80A and the susceptibility of gastric cancer in Chinese Han population in the area of East China. Methods： A case-control study was performed in Yixing city of East China. Two hundred and sixty one patients with gastric adenocarcinoma confirmed by histological examination and 295 age- and sex frequency-matched cancer-free control participated in this study. Genotypes of RFC1-G 80A gene were determined by the polymerase chain reaction-restriction fragment length polymorphism method. The relationship between different genotype and risk of gastric cancer was compared and the influence of smoking and wine drinking were discussed. Results：Logistic regression analysis revealed that compared with wild 80GG genotype individuals carrying 80AA variant genotype had a significantly increased risk （1.79 fold） of gastric cancer （risk increase： 1.79 fold; adjusted OR= 2.79; 95 % CI： 1.77-4.39）. Furthermore, individuals with 80AA genotype had a 2.59-fold risk of gastric cancer （adjusted OR= 2.59; 95 % CI： 1.77-3.80） compared with 80GG/GA genotypes. In addition, the stratification analysis showed that the association was more significant in subgroups of relatively older （≥60 years） （adjusted OR=2.96; 95%CI： 1.63-5.37）, females （adjusted OR= 8.28; 95% CI： 2.95-23.26）, non-smokers （adjusted OR=3.68; 95% CI： 1.94-6.98）, and non-drinkers （adjusted OR=3.08, 95 % CI： 1.76-5.41）. Conclusion：These findings support the hypothesis that the polymorphism of RFC1-G 80A gene may be associated with the susceptibility of gastric cancer in Chinese Han population. Further functional studies in large sample population are needed to confirm our findings.