Association of the insulin gene polymorphism and colorectal cancer

  Introduction: Some studies have determined that polymorphism in insulin gene are associated with increased insulin level and resistant to insulin and also cause to increase risk of colorectal cancer (CRC). The goal of this study was to evaluate incidence of the insulin gene polymorphism (rs689) in an Iranian population and to investigate the role of this polymorphism in increased risk of CRC.   Materials and Methods: Genotyping of the insulin gene were determined in a series of 110 colorectal cancer patients and 110 controls by using polymerase chain reaction and restriction fragment length polymorphism genotyping assays (PCR-RFLP).   Results: P value for genotype AT compared with AA, was 0.052 (OR=1.88, CI=0.99-3.5) and TT versus AA was 0.57 (OR=1.33 CI=0.48- 3.6). The results showed that the insulin gene polymorphism (rs689) is not a predisposing factor to increased risk to CRC (P=0.14). Incidence of mutant allele between patients and controls had no significant differences (OR=1.53 95% CI=0.98- 2.39, Pe=0.057).   Conclusion: These findings suggest that the insulin gene polymorphism (rs689) is not associated with increased risk of CRC.