BsmI polymorphism of the vitamin D receptor gene in hyperparathyroid or hypoparathyroid dialysis patients

Since bone mineral density may be influenced by the polymorphisms of the vi tamin D receptor (VDR) gene, we studied whether VDR genotypes might drive t he progression toward hyperparathyroidism or hypoparathyroidism in patients with end-stage renal disease. On the basis of their parathyroid hormone (P TH) levels, we divided 99 patients undergoing dialysis into 2 groups: 56 pa tients with hypoparathyroidism (PTH < 104 pg/mL [<11 pmol/L]) and 43 with h yperparathyroidism (PTH > 261 pg/mL [>27.5 pmol/L]). The BB polymorphism wa s more frequent in patients with hypoparathyroidism (34%) than ain patients with hyperparathyroidism (16%), but the difference did not reach statistic al significance. Patients with the B allele and BB genotype had a significa ntly lower dialytic age and serum PTH and alkaline phosphatase levels than patients with the b allele and bb genotype. These results suggest that in e nd-stage renal disease, the BB genotype may mark a higher risk of developin g hypoparathyroidism and diminished bone turnover.