中文摘要：

目的探讨X—rayrepair cross—complementing group1（XRCC1）RB99Q基因多态性与结直肠癌易感性的关系。方法通过计算机检索和手工检索，收集有关XRCC1 R399Q基因多态性与结直肠癌易感性关系的文献，筛选出符合条件的文献，应用Meta分析软件对各项研究进行异质性检验，计算合并OR值及其95％可信区间，并行敏感性分析和发表偏倚的评估。结果国内外共有21篇文献纳入研究（结直肠癌组6229例；对照组10692例）。Meta分析结果显示：XRCC1 R399Q基因多态性在整个人群中与结直肠癌无明显的关联性（OR QQvs、RR=1．10，95％CI=0．90～1．35；OR QQ/RQvs.RR=1．02，95％CI=0．90～1．16；OR QQvs.RR/RQ=1．12，95％CI=0．95～1．33）。通过种族的分层分析发现XRCC1 R399Q基因多态性与结直肠癌易感性在亚洲人群和欧洲人群中无差异。结论XRCC1 R399Q基因多态性与结直肠癌间不存在明显的易感性。

英文摘要：

Objective To investigate the association between polymorphism of XRCC1 R399Q and susceptibility of colorectal cancer. Methods Literatures under the same criteria about association between polymorphism of XRCC1 R399Q and susceptibility of colorectal cancer were collected by computer-based retrieval and manual retrieval. The pools ORs with 95% CI were calculated to assess the association strength between polymorphism of XRCC1 R399Q and colorectal cancer risk using Meta methods. Sensitivity and publication bias were evaluated. Results 21 literatures with domestic and foreign 6 229 cases and 10 692 controls were included. The pooled result indicated that no significant association of this polymorphism with colorectal cancer was found （ OR QQvs.RR = 1.10,95% CI = 0.90 - 1.35, OR QQ/RQvs.RR = 1.02,95% CI = 0.90 - 1. 16; OR QQvs, RR/RQ = 1. 12, 95% CI = 0. 95 -1.33）. No significant association was observed in subgroup analysis based on ethnicity. Conclusions There is no relationship between XRCC1 R399Q polymorphism and colorectal cancer susceptibility.