Association of Vitamin D Receptor Polymorphism (VDR rs 2238136) with Colorectal Cancer

Background & Aims: Many studies have demonstrated that Vitamin D has an important role in cell growth and proliferation and vitamin D receptor polymorphism has significant relationship with colorectal cancer (CRC). The aim of this study was to assess the incidence of VDR rs 2238136 polymorphism in Iranian population and to investigate the relationship between this single nucleotide polymorphism (SNP) and increased risk of CRC. Method: In this case-control study, genotyping of vitamin D receptor gene polymorphism (VDR rs2238136) was determined in a series of 112 colorectal cancer patients and 112 controls by using polymerase chain reaction and restriction fragment length polymorphism genotyping assays (PCR-RFLP). Statistical analysis was done through SPSS 16. Results: VDR polymorphism (rs 2238136) had no significant relationship with CRC risk. The result of statistical analysis for the genotype AG compared with GG was OR=0. 59, CI=0.33-1.03 and for AA versus GG was OR=0.8, CI=0.29-2.17. Incidence of mutant allele in patients and controls did not show significant difference (OR=0.74, CI=0.49 -1.13). Conclusion: These findings suggest that VDR (rs 2238136) is not associated with increased risk of CRC. Moreover age, sex and smoking are not predisposing factors for increased risk of CRC.