Functional Genetic Variants of FOXP3 and Risk of Multiple Sclerosis

Background: Multiple sclerosis (MS) is an autoimmune disease that affects the central nervous system (CNS). MS is one of the most common cause of neurological impairment at a young age with a complex etiology. The forkhead/winged helix (FOXP3) gene encodes a transcription factor that plays an important role in the working and progress of regulatory T cells. Loss of the FOXP3 function impairs the suppressor activity of regulatory T (T-reg) cells, which have been reported in MS patients. Objectives: To determine whether rs2232365 and rs3761548 polymorphisms of FOXP3 are associated with the risk of MS in an Iranian population. Patients and Methods: In this case-control study, a total of 384 samples consisting of 190 MS patients and 194 unrelated healthy subjects from the Iranian population were recruited between December 2014 and September 2015. The patients were diagnosed by a neurologist based on McDonald's criteria. The control group had no history or presence of autoimmune diseases. The polymorphisms were genotyped using tetra-ARMS PCR and PCR-restriction fragment length polymorphism (RFLP) techniques. Results: The Rs2232365 G allele was significantly associated with an increased risk of MS (P = 0.0068). In contrast, the allele and genotype frequencies of rs3761548 was not significantly different between the case and control groups (P > 0.05). Conclusions: The functional variant of the FOXP3, rs2232365 A/G, may be considered a substantial risk factor for MS.