Vitamin D receptor alleles and bone physiology.
The vitamin D endocrine system is central to the control of bone and calcium homeostasis. The active hormonal form of vitamin D, 1,25 dihydroxyvitamin D (calcitriol), the circulating level of which is tightly regulated, acts through a specific receptor to mediate its genomic actions on almost every aspect of calcium homeostasis. Because of its transactivation function, it is possible that a small difference in vitamin D receptor level could be amplified into a biologically significant alteration in physiological setpoint. The recent finding that polymorphisms in the vitamin D receptor gene are predictive of bone density (Morrison et al., Nature 367:284-287, 1994) is the first example of an allelic effect in such a homeostatically controlled system. This raises the possibility that such central operators may exist in other regulatory pathways, and could explain a large part of the observed "normal" population distribution that exists for all physiological parameters.
White
C P
CP
Bone and Mineral Research Division, Garvan Institute of Medical Research, St. Vincent's Hospital, Darlinghurst, New South Wales, Australia.
Morrison
N A
NA
Gardiner
E M
EM
Eisman
J A
JA
D000483:Alleles; D000818:Animals; D015519:Bone Density / Q000235:genetics / Q000502:physiology; D016723:Bone Remodeling / Q000235:genetics / Q000502:physiology; D001842:Bone and Bones / Q000502:physiology*; D002117:Calcitriol / Q000502:physiology; D002118:Calcium / Q000378:metabolism; D006706:Homeostasis; D006801:Humans; D018167:Receptors, Calcitriol / Q000235:genetics* / Q000502:physiology
D018167:Receptors, Calcitriol; D002117:Calcitriol; D002118:Calcium