A Safaei - Master of Genetics
F Rostami - Master of Biochemistry
M Arkani - Master of Microbiology
KH Karimi - Master of Microbiology
E Arbabi - Master of Genetic Engineering and Animal Breeding
F KHorshidi - Master of Molecular & Cell Biology
M Iman - Bachelor of Molecular & Cell Biology
M Vahedi - Master of Biostatistics
S.R Mohebi - Ph.D. in Virology
M Vafaei - Research Center for Gastroenterology and liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran. Iran
S.R Fatemi - Associate Professor of Gastrointestinal Diseases, Research Center for Gastroenterology and liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran. Iran
M.R Zali - Professor of Gastrointestinal Diseases, Research Center for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran

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 ۲۲۳۸۱۳۶ 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 rs۲۲۳۸۱۳۶) was determined in a series of ۱۱۲ colorectal cancer patients and ۱۱۲ controls by using polymerase chain reaction and restriction fragment length polymorphism genotyping assays (PCR-RFLP). Statistical analysis was done through SPSS ۱۶. Results: VDR polymorphism (rs ۲۲۳۸۱۳۶) had no significant relationship with CRC risk. The result of statistical analysis for the genotype AG compared with GG was OR=۰. ۵۹, CI=۰.۳۳-۱.۰۳ and for AA versus GG was OR=۰.۸, CI=۰.۲۹-۲.۱۷. Incidence of mutant allele in patients and controls did not show significant difference (OR=۰.۷۴, CI=۰.۴۹ -۱.۱۳). Conclusion: These findings suggest that VDR (rs ۲۲۳۸۱۳۶) is not associated with increased risk of CRC. Moreover age, sex and smoking are not predisposing factors for increased risk of CRC.

Colorectal Neoplasms, Vitamin D, Receptors, Genetic polymorphism