www.elsevier.com/locate/jmcpla Journal of Medical Colleges of PLA 26 (2011) 85–93 A single nucleotide polymorphism in XRCC4 gene is associated with reduced colorectal cancer susceptibility in female Zhang Zhongheng 1* , Hu Weiling 2 1 Jinhua Central Hospital, Jinhua 321000, China 2 Sir Run Run Shaw Hospital, Hangzhou 310016, China Receive 17 March 2011; accepted 05 April 2011 Abstract Objective: To investigate the association of XRCC4 polymorphic variants at G-1394T (rs6869366) with colorectal cancer susceptibility. Methods: In this hospital-based case-control study, the association of XRCC4 polymorphism with colorectal cancer risk in Chinese population was investigated. In total, 171 patients with colorectal cancer and 171 healthy individuals matched for age and gender were selected. The genomic DNAs of the patients and controls were extracted from peripheral blood and the 300 bp target DNA was amplified with Polymerase Chain Reaction. The products were then digested with restriction endonuclease HincII, followed by agarose electrophoresis to identify the genotype. Results: We found a significant difference in the frequency of the XRCC4 G-1394T genotype between the colorectal cancer and control groups in female (1/127 vs 8/122, P<0.05). Those with G/T at XRCC4 G-1394T showed a decreased risk of colorectal cancer susceptibility compared with those with T/T (OR 0.113, 95%CI 0.014–0.932). However, in overall population or in male, there was no significant difference of the distribution between the colorectal cancer and control groups. Conclusion: Our findings suggested that the G allele of XRCC4 G-1394T were associated with decreased risk of colorectal cancer susceptibility in female. Keywords: XRCC4; Colorectal cancer, Single nucleotide polymorphism 1. Introduction Colorectal cancer is a leading cause of cancer-related morbidity and mortality worldwide. *Corresponding author. E-mail address: zh_zhang1984@hotmail.com (Zhang Z.) Nearly 150 000 people were reportedly newly diagnosed with colorectal cancer in the United States alone, which accounts for 10% of all the newly diagnosed cancers [1]. It is recognized that, this cancer progresses through a series of defined histo- pathological stages, going from adnomatous polyp to invasive malignant carcinoma. During this