A Single Nucleotide Polymorphism in the FOXP3 Gene Associated with Behcet's Disease in an Iranian Population

Background: Behcet's Disease (BD) is a rare autoimmune disease that involves the dysfunction of regulatory T cells. FOXP3 is a key transcription factor in the development and function of Treg cells. Recent studies have shown SNPs in the FOXP3 contribute to the susceptibility to some autoimmune disorders. Methods: To clarify the association between the FOXP3 gene and the risk of BD, 50 patients diagnosed with BD and 50 healthy controls from north-western Iran were genotyped by PCR-RFLP (Mun I and Pst I) for two SNPs including rs3761547 (-3499T/C) and rs3761548 (-3279 C/A) in the promoter region of the FOXP3 gene. In addition, a 506 bp nucleotide sequence of FOXP3 promoter was analyzed. Results: The allele -3279 C/A was significantly associated with BD [p = 0.002; odds ratio (OR) = 3.841; 95% confidence interval (Cl) 1.610 - 9.161]; whereas, there was no contribution of the FOXP3 polymorphism -3499T/C to BD [(p = 0.084); (OR = 0.348, 95% CI = 0.101 - 1.195)]. Meanwhile, sequence analysis showed 100% similarity in both controls and BD patient groups. Conclusions: Therefore, the SNP rs3761548 in the FOXP3 gene appears to contribute to the risk of Behcet's disease among the north-western Iranian population.