The impact of osteopontin gene variations on multiple sclerosis development and progression

Osteopontin is a proinflammatory molecule, modulating TH1 and TH17 responses. Several reports suggest its involvement in multiple sclerosis (MS) pathogenesis. We previously reported that OPN gene variations at the 3\u2032 end are a predisposing factor for MS development and evolution. In this paper, we extended our analysis to a gene variation at the 5\u2032 end on the - 156 G > GG single nucleotide polymorphism (SNP) and replicated our previous findings at the 3\u2032 end on the + 1239 A > C SNP. We found that only + 1239 A > C SNP displayed a statistically significant association with MS development, but both + 1239 A > C and - 156 G > GG had an influence on MS progression, since patients homozygous for both +1239A and -156GG alleles displayed slower progression of disability and slower switch to secondary progression than those carrying +1239C and/or -156G and those homozygous for +1239A only. Moreover, patients homozygous for +1239A also displayed a significantly lower relapse rate than those carrying +1239C, which is in line with the established role of OPN in MS relapses