IL-7Ra Association and Genotype-Dependent Severity and Response to IFN-β Therapy in Multiple Sclerosis
Multiple sclerosis (MS) is a neurodegenerative disease arising from interactions of both environmental and genetic factors. The SNP rs6897932 is located in IL‐7Ra gene associated with MS susceptibility in some population. In this study, we investigated the possible association of SNP rs6897932 with MS susceptibility in 157 Iranian MS patients and 152 healthy controls. We also studied genotype-dependent severity and response to IFN-β in MS. Unlike some previous studies, our results clearly demonstrate that there are no significant differences in distribution of the SNP rs6897932 in our chosen Iranian MS patients and controls. Furthermore our results show, Interferon beta (IFN-β) therapy over a period of two years demonstrated an IL‐7Ra genotype-dependent therapeutic effect in MS population. Patients carrying TT or TC genotypes gave a better response to IFN-β treatment, whereas patients carrying the homozygous CC genotype were the worst responders to IFN-β treatment. In other words, despite the lack of linkage the therapeutic response to the severity and progression of MS was related to the genotype of SNP rs6897932 presented in our patient. Therefore, in light of our findings reported here, to reach higher certainties, further studies are needed to associate IL-7Ra gene with the pathogenesis of MS.
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