Polymorphisms of Promoter Region of TNF-α Gene in Iranian Azeri Turkish Patients with Behcet's Disease

Behcet's disease (BD) is a complex chronic relapsing inflammatory disorder of unknown etiology. Alterations of the tumor necrosis factor (TNF) expression related to the polymorphic alleles of TNF gene may implicate a pathogenetic role in increased activity of this cytokine in BD. A current study aimed at investigating the possible association between BD and its clinical features in Iranian Azeri Turks with two functional TNF-alpha gene polymorphisms (at the positions of -238 and -857). A total number of 166 Iranian subjects were enrolled into two different groups; patients with BD (n = 64), and ethnically matched healthy controls (n = 101). The genotype distributions of BD patients and healthy controls were determined. The frequency of TNF-alpha -857C allele was significantly higher in Behcet's patients than that of healthy controls (P = 0.001; odds ratio [OR]= 2.616; 95% confidence interval [CI] = 1.129-6.160), whereas the frequency of TNF-alpha -238A allele was similar in both groups. The sole TNF-alpha haplotype-857C-1031C, was associated with an increase in the risk of developing BD. The TNF-alpha -857C allele was considerably associated with BD in this cohort. The findings of this study, collectively, indicate that TNF-alpha -857C-1031C haplotype located in the promoter region of the gene could exert major influence on the susceptibility to BD.