The HLA rs9267649 and CYP24A1 rs2248359 Variants are Associated with Multiple Sclerosis: A Study on Iranian Population

Background: Studies have shown that MS results from synergism between genetic and environmental factors. As a genetic factor, the rs9267649 variant through the regulatory effect on the HLA-DRB1 expression is involved in the MS development. In addition, vitamin D deficiency through involvement of rs2248359 variant of CYP24A1 has shown to play important role in the risk of MS. Objectives: The aim of this study was to investigate both the HLA rs9267649 and CYP24A1 rs2248359 variants with risk of multiple sclerosis (MS) in Iranian population. Materials and Methods: The rs9267649 and rs2248359 variants were genotyped in 82 Iranian Relapsing-Remitting Multiple Sclerosis (RRMS) patients and 100 matched healthy controls, using the PCR-RFLP method. The genotype and allele frequencies were calculated and statistically analyzed. Results: A significant difference was found in the allele distribution for the both rs9267649 and rs2248359 variants, such that the A allele of rs9267649 and the C allele of rs2248359 were found to be more frequent in MS patients than in the healthy controls (p-value: 0.009, OR: 2.264, 95% CI: 1.211-4.231 and p-value: 0.028 OR: 1.594, 95% CI: 1.052-2.415), respectively. Conclusions: The present research results provide further evidence on the association of the two variants: rs9267649 of the HLA and rs2248359 of the CYP24A1 gene with MS etiology and an increased risk of MS in Iranian RRMS patients. However, further large-scale investigations in various ethnicities and in the functional genomics level are demanded to confirm our findings.