CYP2R1 and type 2 diabetes mellitus: Furthermore, in a recent large Mendelian Randomization meta-analysis of 10 studies from European and Chinese populations (n = 58,312 cases and 370,000 controls), the allelic score of two SNPs from the vitamin D synthesis-related genes, DHCR7 (rs12785878) and CYP2R1 (rs10741657), were shown to be significantly associated with lower risk of T2D (P = .01), where a 25 nmol/l higher 25(OH)D concentration was associated with a 14% lower risk of diabetes [26].