Vitamin-D receptor genotype does not predict bone mineral density, bone turnover, and growth in prepubertal children

We examined whether the polymorphism for Bsml restriction enzyme in the vit amin-D receptor (VDR) gene influenced radial (distal third) and lumbar (L2- L4) bone mineral density (BMD), phospho-calcium metabolism (calcium, phosph ate, intact parathyroid hormone, 25-hydroxyvitamin D, and 1,25-dihydroxyvit amin D), biochemical markers of bone formation (osteocalcin and carboxy-ter minal propeptide of type-1 procollagen) and bone resorption (carboxy-termin al telopeptide of type-1 collagen and urinary cross-linked N-telopeptides o f type I collagen), insulin-like growth factor I and insulin-like growth fa ctor-binding protein 3, and growth in 209 healthy prepubertal children (112 males and 97 females) aged 7.1-10.0 years. Genotype frequencies were BE 19 %, Bb 46%, and bb 35% in the pooled group of children. Clinical findings, d ietary calcium intake, calcium density, and physical activity rate were not different (p NS) among the VDR genotypes. Radial BMD, lumbar BMDarea and l umbar BMD adjusted for the apparent bone volume (BMDvolume), and all the bi ochemical parameters did not differ (p NS) in relation to the VDR genotype. in conclusion, our data show that polymorphism for Bsml restriction enzyme in the VDR gene is not associated with radial and lumbar BMD, parameters o f phospho-calcium metabolism and bone turnover, growth hormone-dependent gr owth factors, and growth in prepubertal children.