Effect of TT genotype of the vitamin D receptor gene on bone mineral density in dialysis patients

Abstract

Aim: to evaluate the effect of TaqI genotypes of vitamin D receptor (VDR) gene polymorphism on bone mineral density (BMD) and the risk for secondary osteoporosis (OP) in patients on programmed hemodialysis. Subjects and methods. Eighty-two patients treated with long-term hemodialysis were examined. Along with physical examination, osteodensitometry was carried out and VDR gene polymorphism was studied in all the patients. Results. OP in the study skeletal parts was more common in the TT-genotype group. The serum concentration of intact parathyroid hormone and the activity of alkaline phosphatase were also higher in the TT-genotype group. However, the differences were statistically insignificant between the TT-, Tt-, and tt- genotype groups. BMD was lowest in each study skeletal parts in the TT-genotype group and this difference was statistically significant in the proximal femur, which was estimated by the Z index (p = 0.02). Conclusion. The results of the present study confirm the hypothesis that the VRD gene is a genetic determinant of bone metabolism in patients with chronic renal disease who receive long-term hemodialysis.

Keywords

• vdr gene polymorphism
• osteoporosis
• hyperparathyroidism
• hemodialysis