TNFRSF11A and diabetes mellitus: Hierarchical clustering of SNPs in the OPG, RANKL, and RANK genes identified OPG 245T/G and OPG 1217C/T with a nearly identical pattern of distribution; meanwhile, RANK 421C/T and OPG 6890A/C also cluster together with OPG 245T/G and 1217C/T, and the CDF has the most considerable number of patients in the third cluster, and an equal number of patients with DM in the second cluster [40].