MS is an autoimmune disease and interleukin 13 (IL-13) has been proposed to be an important neuroprotective mediator in MS. Because of plausible effect of single nucleotide polymorphisms (SNPs) in expression level or biological activity of any cytokine, we sought to investigate association of IL-13 SNPs, C-1112T, A-1512C and G+2044A, with risk to MS. Sixty-eight RRMS patients and 110 healthy controls were involved in this study. After extraction of genomic DNA, frequency of genotypes and alleles were determined by PCR-RFLP and data were analyzed statistically. Results showed significant higher frequency of CC, CC, and AA genotypes and C, C, and A alleles of -1112CT, -1512AC and +2044GA SNPs respectively, in patients group. There was significant association between -1112C allele with onset age of MS. No significant association was seen between any of genotypes or alleles with expanded disability status scale (EDSS) of patients. Our findings showed significant association between three studied SNPs of IL-13 with susceptibility to MS in Iranian patients. More studies should be done on other IL-13 SNPs, and also polymorphisms of IL-13 receptor and other cytokines to determine the exact role of SNPs in protecting or predisposing of individuals for MS.
Keywords: Multiple sclerosis; PCR; RFLP; interleukin 13; polymorphism.