Polymorphisms of Vitamin D Receptor Gene (Apa І وFok І) and its Association with Serum Vitamin D and Parathyroid Hormone Levels in Hemodialysis Patients

Abstract

Background & Objectives: Vitamin-D receptor (VDR), plays a key role in the development of cardiovascular diseases in hemodialysis patients via the modulation of the serum levels of calcium and parathyroid hormone. In this study, we aimed to determine the genetic association of VDR gene polymorphisms with serum levels of vitamin D, parathyroid hormone and fetuin-A in hemodialysis patients. Material and Methods: Forty six hemodialysis patients and 43 control cases were studied. VDR Genotyping was determined by polymerase chain reaction-restriction fragment length polymorphism. The serum levels of iPTH, Fetuin-A and Vit D were measured by enzyme-linked immunosorbent assay. Results: There was no significant difference in the genotype frequencies between two study groups in both Fok І and Apa І polymorphisms (p=0.2). There was significant difference in serum iPTH levels in Fok І polymorphism (p=0.02) and Vit D levels in Apa І polymorphism (p=0.04). Although a significant positive correlation between iPTH and Vitamin D levels in aa genotype of patients (p=0.02, r=0.4) and Vit D and Fetuin-A levels in FF genotype of control group (p=0.001, r=1) was seen. Conclusion: Polymorphisms of VDR gene Fok І and Apa І play a key role in the development of cardiovascular diseases in hemodialysis patients.