Multiple sclerosis and susceptibility to cardiovascular diseases: Implications of ethnicity-related interleukin-17A gene polymorphism?

There are conflicting findings on whether patients with MS are at more or less risk of vascular comorbidities as compared to the general population. The worldwide incidence and prevalence of cardiovascular diseases (CVD) in the MS patients has been reported to vary substantially by region. Inflammation and demyelination in MS seem to be due to an autoimmune process mediated by IL17 secreting Th17 cells. Genotypic and allelic frequencies of IL17A and IL17F gene polymorphisms seem to confer risk to MS across populations. Increased serum levels of TH17 cells and IL-17 have been connected with atherogenesis. Ethnic-specific IL17A gene haplotypes have been associated with the risk of developing atherosclerosis and premature coronary artery disease. The co-occurrence of CVD with MS might be due to ethnicity-related IL-17 gene polymorphism implying geographic and population heterogeneities. Ethnic-specific IL17 gene polymorphism may explain the conflicting results both on the roles of IL17 and Th17 cells in atherosclerosis development and about the epidemiology of CVD in MS population across countries. Genomic and proteomic studies are required to assess the possibility to use polymorphisms of IL17 gene as biomarkers of racial susceptibility to CVD in MS.