The protective role of TBX21-1514T>C polymorphism in susceptibility to multiple sclerosis.

Background: As a T-cell mediated disease, multiple sclerosis (MS) pathogenesis might be associated with the immune system and its involved genes. TBX21, which encodes T-bet transcription factor, is a critical regulator of the commitment to the Th1 lineage and Interferon gamma (IFNγ) production. Investigation of the association of -1514T > C polymorphism located upstream of TBX21 gene with MS susceptibility is reasonable due to its demonstrated significant association with some other immune-mediated diseases. Methods: We analyzed the genotype frequencies of -1514T > C polymorphism between 248 Iranian patients with MS and 163 matched healthy controls. By applying polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP)- technique, the single-strand conformation patterns of the amplicons were compared and sequenced. Results: Strong association between the wild -1514T allele and MS susceptibility was found with the allelic frequency of 99.6% in patients vs. 95.1% in controls (P = 0.002), and the CC genotype frequency of the TBX21 polymorphism (-1514T > C) reported potential protective effect against the disease (P = 0.014). Conclusion: The TBX21-1514T > C polymorphism confers possible protective effect on MS in Iranian population. Further comprehensive studies in different settings are required to clarify the exact role of TBX21 gene in MS disease.