The distribution of two different vitamin D receptor polymorphisms (BsmI and start codon) in primary hyperparathyroidism

Introduction. The bb genotype of the BsmI polymorphism of the vitamin D rec eptor (VDR) is more common in primary hyperparathyroidism (HPT) than in the general population in Swedish and German women. However, little is known a bout the association of HPT with the start codon polymorphism of the VDR (d efined by FokI). Objective. To study the distribution of the VDR genotypes in a group of wom en with HPT compared with a control group. The bone mineral density (BMD) o f different genotypes was also investigated.,Methods. VDR alleles were type d by polymerase chain reaction (PCR) assay around the polymorphic BsmI or F okI restriction sites in 67 control women (48.5 +/- 10 years) and 53 women with HPT (61.4 +/- 11 years). They were all Caucasian and born in the Canar y Islands. Lumbar and proximal femur BMDs were measured by dual S-ray absor ptiometry (DXA) and quantitative computed tomography (QCT). Results, The 'bb' genotype was equally frequent in controls and HPT subject s (46.3 and 45.3%, respectively). There was a trend towards a lower prevale nce of the FF genotype amongst women with HPT as compared with controls (41 .5 vs. 57.1%; P = 0.09). BMD was lower in patients with HPT compared with c ontrols in the lumbar spine and the proximal femur. Conclusions, The association of the BsmI polymorphism of the VDR gene with HPT is not applicable to all geographical areas. In Canarian postmenopausal women suffering from HPT, VDR genotype distribution is similar to that fou nd in controls. A possible association of HPT with the FokI polymorphism de serves further investigation.