Vitamin D receptor gene polymorphism and bone mineral density in patients with type 2 diabetes mellitus

Objective To explore the relationship between vitamin D receptor (VDR) gene polymorphisms and bone mineral density (BMD) in patients with type 2 diabe tes mellitus (DM) and to better understand the pathogenesis of osteoporosis . Methods Ninety seven patients with type 2 DM were recruited for this study. BMD was measured by single photon absorptiometry at the lower one third of the nondominant radius and ulna. Polymorphisms of the VDR gene were analyz ed by DNA amplification with polymerase chain reaction ( PCR) and endonucle ase digestion with Bsm I. Results The respective frequencies of VDR genotypes were BB 18.6%, Bb 27.8% and bb 53.6%. The Z scores of the three groups were - 1.57 +/- -0.60, - 1. 45 +/- - 0.67 and - 1.41 +/- - 0.81, respectively. Although the BMD of the Bb genotype DM patients was higher than that of BB genotype DM patients and lower than that of bb genotype DM patients, there were no significant diff erences. Conclusion These findings suggest a small influence of VDR gene polymorphis m on the BMD of patients with type 2 DM. Further study on the value of VDR genotypes in the pathogenesis of osteoporosis in diabetes mellitus is still needed.