Such single nucleotide polymorphisms (SNPs) have been identified within a Mendelian randomization study of MS patients and healthy controls near the following genes: GC (vitamin D-binding protein), DHCR7 (7-dehydrocholesterol reductase, enzyme catalyzing the conversion of cholesterol to vitamin D precursor), CYP2R1 (vitamin D-25-hydroxylase), and CYP24A1(1,25-dihydroxyvitamin D-24-hydroxylase, degrades vitamin D) [53]. This evidence concerns the gene DHCR7 and myeloid sarcoma.