Osteoporosis is now a major health problem because of the increasing elderly population and related osteoporosis fractures. Recently, it has been suggested that lower bone mass with/and high bone turnover rate is considered to be important in the
developing of osteoporosis, and so there has been many efforts to identify the risk factors which is considered to cause lower bone mass and high bone turnover.
Osteocalcin, the most abundant noncollagenous protein in bone, is a marker of bone turnover and its synthesis is induced by calcitriol(the active form of vitamine-D) through the vitamine-D receptor(VDR) and a specific vitamine D-responsive
element
in
the osteocalcin gene promoter. Serum concentrations of osteocalcin are under the strong genetic influences and may reflect allelic variation in VDR gene. Therefore, the present study were designed to find the relationships among the polymorphisms
of
Vitamine-D receptor gene, bone mineral density and bone markers.
We analysed the restriction fragment length polymorphisms of VDR gene with Bsm I endonuclease enzyme in relation to bone mineral density by using DEXA(dual energy X-ray absorptiometry, QDR-2000) and bone markers, especially serum osteocalcin
concentrations in 356 pre- and postmenopausal Korean women.
The frequence of RFLPs of VDR gene is 3.3% in BB type, 10.1% in Bb type, 86.6% in bb type. The concentrations of osteocalcin, alkaline phosphatase, procollagen-C and urinary deoxypyridinoline/ creatinine were found to be higher in postmenopausal
than
premenopausal women and the levels of BMD were lower in postmenopausal than premenopausal women.
The BB type, which is known to have a strong genetic determinant, is less frequently encountered in Korean women and does not correlate with levels of bone markers and bone mineral density. Even though the number of women with BB type is small,
we
noted
the mean serum level of each bone marker was greater in postmenopausal women with BB type than in premenopausal women with the same genotype.
In conclusion, this may suggest a partial agreement of our data with that of Australlian group and that we have to try to find out another genotype specifically related with lower bone density in Korean women(J Kor Soc Endocrinol 10:249~261,
1995)
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