Impact of Genetic Polymorphisms in the Interleukin-18 and Interleukin-21 Genes on the Risk and Clinical Outcomes of Multiple Sclerosis

Abstract To study the association between IL-18-137G/C (rs187238) and IL-21-1472G/T (rs2055979) single nucleotide polymorphisms (SNPs) with the risk of MS, the disease progression, as well as the clinical features. 271 Egyptian individuals have participated in this present search, of whom 99 cases and 140 were unrelated healthy controls. For the IL-18-137G/C SNP, the GC genotype and C allele were linked to susceptibility to MS, and the GC and CC genotypes and C allele were linked to a higher risk of developing progressive MS. Regression investigation further strengthened the notion that this SNP is a predictor of the disability of the disease according to the Disability Status Scale (EDSS) values. For the IL-21-1472G/T SNP, the TT genotype and T allele were associated with the decreased risk of progressive MS in the Egyptian cohort when comparing the two diseased forms; however, they were not associated with the disability progression and severity of the disease. The IL-18-137G/C SNP could be a possible risk factor for the susceptibility and progression of MS. In contrast, the IL-21-1472G/T SNP could protect against progressive MS.