CYP27A1, CYP24A1, and RXR-α Polymorphisms, Vitamin D, and Multiple Sclerosis: a Pilot Study

Multiple sclerosis (MS) is a neurodegenerative autoimmune disease resulting from a complex interaction of genetic and environmental factors. Hypovitaminosis D seems to contribute to MS susceptibility as both an environmental and a genetic risk factor. The aim of our study was to investigate the association of SNPs in CYP27A1, CYP24A1, and RXR- α genes, vitamin D status, and MS risk. We performed a nested case-control study on patients with multiple sclerosis and healthy controls. Serum 25(OH)D₃ levels and genotyping of CYP27A1, CYP24A1, and RXR-α -SNPs were investigated both in MS patients and in healthy controls. Serum 25(OH)D₃ levels were measured by a high-performance liquid chromatography (HPLC). Molecular analysis was performed by real-time PCR. The distribution of genotypic and allelic frequencies was not significantly different between patients and controls, except for rs2248137 CYP24A1. In particular, CC genotype (C minor allele) showed a higher frequency in MS patients in comparison to healthy controls. Moreover, we observed significantly lower serum 25(OH)D3 levels in MS patients with CC genotype in comparison to MS patients with GG and GC genotype. The findings of our study suggest a role of rs2248137 CYP24A1 in multiple sclerosis risk.