title: Association of Tumor Necrosis Factor Alpha Gene Polymorphisms with Inflammatory Bowel Disease in Iran.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: 1. Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science , Tehran, Iran.
authors.forename: Nosratollah
authors.initials: N
authors.lastname: Naderi
authors.affiliation: 2. Imam Khomeini Hospital, Tehran University of Medical Science , Tehran, Iran.
authors.forename: Alma
authors.initials: A
authors.lastname: Farnood
authors.affiliation: 1. Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science , Tehran, Iran.
authors.forename: Tahereh
authors.initials: T
authors.lastname: Dadaei
authors.affiliation: 1. Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science , Tehran, Iran.
authors.forename: Manijeh
authors.initials: M
authors.lastname: Habibi
authors.affiliation: 2. Imam Khomeini Hospital, Tehran University of Medical Science , Tehran, Iran.
authors.forename: Hedie
authors.initials: H
authors.lastname: Balaii
authors.affiliation: 1. Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science , Tehran, Iran.
authors.forename: Farzad
authors.initials: F
authors.lastname: Firouzi
authors.affiliation: 1. Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science , Tehran, Iran.
authors.forename: Aydin
authors.initials: A
authors.lastname: Mahban
authors.affiliation: 1. Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science , Tehran, Iran.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Soltani
authors.affiliation: 1. Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science , Tehran, Iran.
authors.forename: Mohammadreza
authors.initials: M
authors.lastname: Zali
keywords: Crohn’s disease; SNPs; TNF-α gene; Ulcerative colitis