View article

Bone mass and its mineral content are under genetic control. The vitamin D receptor (VDR) gene has been shown to be a major locus for genetic effects on bone mineral density (BMD), and polymorphisms in this gene accounted for a large proportion of genetic variance in BMD in an Australian population. In this study, we investigated whether similar associations are present in a North American population. We studied 139 normal healthy women (age 53.2 ± 14.5, mean ± SD) and 43 severely osteoporotic postmenopausal women (age 65.8 ± 5.9). In the 127 of them with complete genetic studies, the distribution of genotypes, determined by polymerase chain reaction on leukocyte DNA samples, agreed closely with that in the Australian population. BMD was strongly related to age and weight, and, thus was adjusted for these parameters prior to genetic analysis. We found that age modulated the effect of VDR …