RELATION OF COMMON ALLELIC VARIATION AT VITAMIN-D-RECEPTOR LOCUS TO BONE-MINERAL DENSITY AND POSTMENOPAUSAL BONE LOSS - CROSS-SECTIONAL ANDLONGITUDINAL POPULATION STUDY

Objective-To determine whether common allelic variation at the vitamin D receptor locus is related to bose mineral density and postmenopausa l bone loss. Design-Cross sectional and longitudinal population study. Setting-Outpatient clinic in research centre. Subjects-599 healthy wo men aged 27 to 72 and 125 women with low bone mass aged 55-77 had bone mineral density measured once in the cross sectional study. 136 women aged 45-54 were followed up for 18 years in the longitudinal study. M ain outcome measures-Bone mineral density measured at the lumbar spine , hip, and forearm and rate of bone loss at different times over 18 ye ars in relation to vitamin D receptor genotype as defined by the endon ucleases ApaI, BsmI, and TaqI. Results-Vitamin D receptor genotype was not related to bone mineral density at any site. The maximum differen ce between homozygotes was 1.3% (P = 0.33, n = 723). Women with low bo ne mineral density had almost the same genotype frequencies as the wom en with normal bone mineral densities. Vitamin D receptor genotype was not related to early postmenopausal bone loss from age 51 to 53 (mean (SD) total loss at the lower forearm -3.6% (3.6%)), late postmenopaus al bone loss from age 63 to 69 (at the hip -6.2% (8.7%)), or to long t erm postmenopausal loss from age 51 to 69 (at the lower forearm -24.5% (11.4%)). Conclusion-Common allelic variation at the vitamin D recept or locus as defined by the endonucleases ApaI, BsmI, and TaqI is relat ed neither to bone mineral density nor to the rate of bone loss in hea lthy postmenopausal Danish women.