Association between p53 and p21 genes polymorphisms and ulcerative colitis in an Iranian population

Abstract

Ulcerative colitis is an inflammatory disease characterized by ongoing mucosal and submucosal changes, starting from the rectum and spreading to proximal regions. The p53 gene is considered as the most important tumor suppressor gene, encoding for a 53 k Dalton phosphoprotein, whose natural function is to protect the genome against damages by activation of the P21 protein. The P21 protein, in turn, causes cell cycle arrestment at the G1/S phase through inhibition of the CDK1 and CDK2 activity, and thus, permits DNA repair.In this study, we investigated the association of the p53 codon 72 and p21 codon 31 polymorphisms with ulcerative colitis in the north of Iran using RFLP-PCR assay. A total number of 174 patients with intestinal ulcers and 82 healthy controls were genotyped for p53 codon 72 and p21 codon 31 polymorphisms.The Arg/Arg genotype of p53 gene codon 72 was associated with an increased risk for ulcerative colitis (OR, 4.074; 95% CI,5.874–1.800), compared with the Pro/Pro genotype. Also, the Ser/Ser genotype of p21 gene codon 31 was associated with an increased risk of ulcerative colitis (OR, 3.175; 95% CI, 4.875–1.700), compared with the Arg/Arg genotype. Also, we found a significant relationship between ulcerative colitis with age, metastasis, and cancer stage, but no relationship with gender was found )Chi-Square p < 0.05).The findings suggest that genetic polymorphisms of the p53 gene codon 72 and p21 gene codon 31 were significantly associated with ulcerative colitis and could be used as a prognostic marker for ulcerative colitis and gastrointestinal malignancies.