CYP27B1 and diabetes mellitus: The possible association between low vitamin D levels and CVD, diabetes, cancer, and inflammatory disorders may be due to a large number of genes acting under the control of 1α,25(OH)2D. It may also be caused by the fact that the vitamin D receptor (VDR) and CYP27B1 1α-hydroxylation enzyme expression are located in most tissues and cells, including vascular endothelium and cardiomyocytes [102,103].