A mendelian randomization study conducted in China [42] investigated the effect of genetically lowered vitamin D levels on MetS and its related traits using a GRS constructed from four SNPs commonly associated with vitamin D, including rs12785878 in DHCR7, rs10741657 in CYP2R1, rs2282679 in GC and rs6013897 in CYP24A1. This evidence concerns the gene CYP2R1 and metabolic syndrome.