Role of IL-2 in development and course of multiple sclerosis is influenced by HLA-DRB alleles in an Iranian population

Background and aims: Recent genome wide association studies have shown that cytokine gene polymorphisms might play an important role in the pathogenesis of multiple sclerosis (MS). We have studied the impact of IL-2/-330 single nucleotide polymorphism (SNP) and its combination with HLA-DRB alleles in Iranian population. Materials and methods: We used sequence specific primer-polymerase chain reaction (SSP-PCR) to profile the genetic polymorphism of 241 MS patients and 264 healthy controls from Iranian population. HLA-DRB alleles were determined by standard manufacture protocol for all cases. The 2-sided Fisher’s exact test was applied to calculate the significance of differences of allele and genotype frequencies between two groups and P-values less than 0.05 were assumed to be significant. Results:Analysis of IL-2 promoter polymorphisms showed significant differences between controls and patients. We observed a significant increase of T allele and T/T genotype in the -330 position of IL-2 gene. However, this polymorphism didn’t affect onset, type or severity of disease. Beside HLA-DRB alleles, T/G genotype was less frequent among HLA-DRB1*01, DRB1*16, DRB1*07, DRB1*11, DRB1*13, DRB1*14, DRB3*01, DRB4*01 and DRB5*01 positive patients (p<0.05). In addition, DRB1*0103 allele besides T/T genotype was significantly associated with MS (15 patients vs. 0 controls, p