The central role of the biologically active vitamin D is to regulate calcium homeostasis through increasing bone mineralization and intestinal calcium absorption. Moreover, vitamin D is found to be related to glucose metabolism, therefore vitamin D deficiency and vitamin D receptor (VDR) gene polymorphism may provoke type 2 diabetes mellitus (T2DM) and osteoporotic fractures as well.
This case control study was conducted on 90 premenopausal females. Serum vitamin D2, total calcium, albumin, ionized calcium and fasting plasma glucose were assayed. VDR gene TaqI single nucleotide polymorphism was assessed using polymerase chain reaction (PCR) using DNA isolated from the collected whole blood.
Results showed that hyperglycemia, hypovitaminosis D2 and low level of total calcium were observed in secondary T2DM osteoporotic fractures. G allele was significant in the control group compared to patients with secondary T2DM osteoporotic fractures. Accordingly, we deduce that the recessive G allele has a protective role against osteoporotic fractures in T2DM females.