Predisposing role of vitamin D receptor (VDR) polymorphisms in the development of multiple sclerosis: A case-control study

Multiple sclerosis (MS) is a chronic inflammatory, demyelinating, and neurodegenerative disease of the central nervous system (CNS) with a complex etiology. Given the Vitamin D receptor (VDR) gene, it is considered an outstanding risk component associated with MS. The aim of the present study has been to explore and emphasize the role of ApaI, BsmI, TaqI and FokI polymorphisms of VDR gene in susceptibility to MS in an Iranian case-control population including 160 patients and 150 healthy controls. All cases were clinically diagnosed with relapsing-remitting (RR) form, and the controls were age, gender, and race matched which were completely in agreement with the case group. PCR-R FLP was conducted for all the SNPs genotyping. The findings of the study showed a significant difference in allele frequency between the cases and controls for ApaI (p<0.0002), BsmI (p<0.0002) and TaqI (p<0.0001), while no significant difference was observed for FokI (P>0.0125). The results also showed that AA genotype polymorphism of ApaI and BsmI (OR=4.6 and OR=2.52, respectively), CC genotype of TaqI (OR=2.41) and AC genotype of ApaI (OR=1.79) are associated with the disease status. Nevertheless, the results revealed the protective role of TT genotype of TaqI (ORs<1), CC genotype of Apal, and GG genotype of BsmI (ORs<1). VDR polymorphisms seem to have a notable connection with MS pathogenesis, however, study of more big population and functional work on the gene structure and its function are recommended.