Association of VDBP rs4701 variant, but not VDR/RXR-α over-expression with bone mineral density in pediatric β-Thalassemia patients (original) (raw)

Introduction: The reduced rate of bone formation despite the availability of vitamin D has been reported in β-thalassemia. This suggests genetic factors together with environmental one can be implicated in this condition. Since vitamin D binding protein (VDBP) maintains bioavailability of vitamin D which binds to vitamin D receptor (VDR)-retinoid X receptor alpha (RXRA) heterodimer to exert its molecular actions, we speculated that vitamin D metabolic-axis expression signature and variants could be potential molecular candidates for bone turnover/disease in thalassemia. To this end, this study aims to analyze VDR/RXRA expression signature, and two VDBP variants in a pilot sample of Egyptian β-thalassemia children in correlation with bone mineral density (BMD). Patients and methods: Forty-four β-thalassemia children and 40 unrelated controls were enrolled. The serum bone chemistry profile was measured. Peripheral blood mononuclear cells (PBMN) VDR/RXRA expression levels were quantif...