Vitamin D receptor gene Tru9I polymorphism and risk for incidental sporadic colorectal adenomas

• Published in: World journal of gastroenterology : WJG Vol. 11; no. 31; pp. 4794 - 4799
• Main Authors: Gong, You-Ling, Xie, Da-Wen, Deng, Zong-Lin, Bostick, Roberd M, Miao, Xi-Jiang, Zhang, Jin-Hui, Gong, Zhi-Hong
• Format: Journal Article
• Language: English
• Published: United States Baishideng Publishing Group Inc 21.08.2005
• Subjects: Adenoma - epidemiology; Adenoma - genetics; Alcohol Drinking; Anti-Inflammatory Agents, Non-Steroidal - adverse effects; Basic Research; Colorectal Neoplasms - epidemiology; Colorectal Neoplasms - genetics; Female; Gene Frequency; Genotype; Humans; Male; Middle Aged; Polymorphism, Genetic; Receptors, Calcitriol - genetics; Risk Factors; Smoking; Tru9I; 受体基因; 基因多态性; 结直肠癌; 维生素D
• ISSN: 1007-9327; 2219-2840
• DOI: 10.3748/wjg.v11.i31.4794

AIM： Recent laboratory and epidemiological studies suggest that vitamin D is a potential agent for colorectal cancer prevention. Its function is partially mediated by the vitamin D receptor （VDR）. The aim of this study was to investigate whether a novel G （allele ‘U’g〉A （allele ‘u’ polymorphism （Tru9I） in the VDR intron 8 region is associated with risk for colorectal adenoma in a colonoscopy-based case-control study. METHODS： Genotyping for a total of 391 subjects was carried out through PCR and restriction fragment length polymorphism. RESULTS： The frequencies of ‘U’ and ‘u’ alleles were 89.3% and 10.7%, respectively. The ‘Uu’ and ‘uu’ genotypes were associated with decreased risk for adenoma （OR, 0.71; 95%CI, 0.40-1.25）. The inverse association was more pronounced for multiple adenomas and adenomas that were larger had moderate or greater dysplasia, or were sessile： the odds ratios （ORs） were, 0.51 （95%CI, 0.21-1.24）, 0.37 （95%CI, 0.11-1.28）, 0.68 （95%CI, 0.33- 1.41）, and 0.36 （95%CI, 0.13-0.97） respectively. In joint/ combined analyses, inverse associations were more obvious among those who had at least one ‘u’ allele and also were younger （OR, 0.60; 95%CI, 0.26-1.37）, women （OR, 0.38; 95%CI, 0.17-0.88）, did not smoke （OR, 0.39; 95%CI, 0.13-1.23）, or took NSAID （OR, 0.38; 95%CI, 0.12-1.25）, but no evidence existed for interactions with calcium or vitamin D intake.CONCLUSION： Our findings suggest that the VDR TrugI polymorphism may be associated with lower risk for colorectal adenoma, particularly in interaction with various risk factors, but not with calcium or vitamin D.