These included two clusters of 3 index SNPs, each associated with 25(OH)D concentrations (GC rs2282679, DHCR7 rs12785878, CYP2R1 rs12794714), and T2D (IGF2BP2 rs1470579, TCF7L2 rs7903146, and KCNQ1 rs2237896), respectively. This evidence concerns the gene CYP2R1 and type 2 diabetes mellitus.