association of tumor necrosis factor alpha gene polymorphisms with inflammatory bowel disease in iran.

inflammatory bowel disease (ibd) is a chronic disease of unknown etiology, in which genetic factors, seem to play an important role in the disease predisposition and course. assessment of tumor necrosis factor (tnf-α) gene polymorphisms in many populations showed a possible association with ibd. considering the genetic variety in different ethnic groups, the aim of the present study was to investigate the association of five important single nucleo-tide polymorphisms (snps) in the promoter region of (tnf-α) gene with ibd in iran.in this case-control study, 156 ulcerative colitis (uc) patients, 50 crohn's disease (cd) patients and 200 sex and age matched healthy controls of iranian origin were enrolled. the study was performed during a two year period (2008-2010) at taleghani hospital, shahid beheshti university of medical sciences, tehran, iran. dna samples were evaluated for (tnf-α) gene polymorphisms (including -1031, -863, -857, -308 and -238) by pcr and rflp methods.the frequency of the mutant allele of -1031 polymorphism was significantly higher in iranian patients with crohn's disease compared to healthy controls (p=0.01, or=1.92; 95% ci: 1.14-3.23). none of the other evaluated polymorphisms demonstrated a significant higher frequency of mutant alleles in iranian ibd patients compared to controls.among the five assessed (snps), only -1031 polymorphism of (tnf-α) gene may play a role in disease susceptibility for crohn's disease in iran. this pattern of distribution of (tnf-α) gene polymorphisms could be specific in this population.