中文摘要：

目的探讨HER-2原癌基因Ile655Val多态性与结直肠癌易感性的相关性，及其在自然人群中的分布频率。方法应用病例对照研究，对浙江省嘉善县292例结直肠癌患者和842名健康对照者采用聚合酶链反应-限制性片段长度多态性方法检测HER-2基因密码子655基因型。结果结直肠癌组HER-2基因Ik／val＋Val／Val基因型频率（25．34％）和Val等位基因频率（13．36％）均显著高于对照组（18．41％和9．74％）（P〈0．05）。与Ile／Ile基因型携带者相比，Ile／Val＋Val／Val基因型携带者患结直肠癌的风险增加（OR=1．54，95％CI：1．11～2．14）。HER-2基因多态性与吸烟、饮酒的交互作用0R值分别为1．43（95％CI：0．88～2．30）和1．29（95％CI：0．73～2．29）。结论HER-2基因Ile655Val多态性与结直肠癌易感性相关，但是这种多态性与吸烟、饮酒在结直肠癌发生中不存在交互作用。

英文摘要：

Objective To explore the distribution of HER-2 genetic polymorphism at codon 655 and its association with susceptibility of colorectal cancer in Chinese. Methods A population-based case-control study was carried out. 292 patients with colorectal cancer and 842 healthy controls were interviewed. Meanwhile, the genetic polymorphism of HRE-2 was detected using polymerase chain reaction-restriction fragment length polymorphism. Results The frequencies of Ile/Val-Val/Val genotypes and Val allele were both higher in cases（25. 34% and 13. 36%） than those in controls（18. 41% and 9. 74%）（P〈0. 05）. Compared with Ile/Ile genotype, Ile/Val＋ Val/Val genotypes were significantly associated with colorectaI cancer （ORadjsted = 1. 54, 95% CI： 1. 11-2. 14）. The adjusted odds ratio of interactions between this polymorphismand smoking, alcohol drinking were 1.43 （95%CI： 0.88-2.30） and 1. 29 （95%CI： 0. 73- 2.29）, respectively. Conclusion The present findings suggest that HER-2 genetic polymorphism at codon 655 may he associated with the risk of colorectal cancer in Chinese. In addition, there are no interactions between this polymorphism and smoking, alcohol drinking, respectively.