Association of vitamin D receptor gene Cdx2 polymorphism with bone markers in Turner syndrome patients

Abstract

Background: Turner syndrome (TS) patients usually have low bone mineral density (BMD) and increased risk of osteoporotic fractures. We have previously demonstrated an association of bb (BsmI polymorphic site) and ff (FokI polymorphic site) vitamin D receptor (VDR) genotypes with reduced BMD in TS patients. Aim: To analyze the relationship between VDR-Cdx2 polymorphism and BMD as well as bone metabolic variables in TS patients. Methods: Fifty five TS patients and 59 control women were studied. VDR-Cdx2 genotypes were determined by using TaqMan probes in a real time thermocycler. Lumbar and femoral BMD were determined by DEXA and serum intact parathyroid hormone, osteocalcin and beta-CrossLaps by electrochemiluminescence. Results: Patients with genotype GG had higher levels of both osteocalcin and beta-CrossLaps as compared to patients with genotype GA. Conclusion: Patients carrying genotype GG have higher levels of bone formation and resorption markers, which indicates a more active bone turnover that could impact on their future bone mineral density.