Vitamin D Receptor Gene Polymorphisms, Bone
Mineral Density and Bone Turnover: FokI Genotype is Related to
Postmenopausal Bone Mass
K. ZAJÍČKOVÁ1,
I. ŽOFKOVÁ1, R. BAHBOUH2
, A. KŘEPELOVÁ3
1Institute of Endocrinology,
2Faculty of Philosophy and Department of 3Biology and Genetics,
First Faculty of Medicine, Charles University, Prague, Czech
Republic
Received November 5, 2001
Accepted January 28, 2002
Summary
The relationship between vitamin D receptor (VDR) intragenic
polymorphisms FokI, BsmI, ApaI and TaqI and bone mineral density
(BMD) or biochemical markers of bone remodeling were
investigated in 114 Czech postmenopausal women, on the average
62.5±8.9 years of age. Restriction fragment length polymorphisms
in the VDR gene were assessed by PCR amplification and digestion
with restriction enzymes FokI, BsmI, ApaI, and TaqI recognizing
polymorphic sites in the VDR locus. Bone mineral density was
measured at the lumbar spine and at the hip by dual-energy X-ray
absorptiometry (DEXA, g/cm2). After adjusting for age and the
body mass index (BMI), subjects with the ff genotype had 9.4 %
lower BMD at the hip than those with the Ff genotype (p=0.0459,
Tukey´s test). FF individuals had an intermediate BMD at the
hip. A similar pattern of lower lumbar spine BMD was also found
in ff individuals, but it did not reach statistical
significance. There was no relationship between BsmI, ApaI and
TaqI VDR polymorphisms and BMD at any skeletal site. Subjects
with Aa (ApaI) genotypes had higher levels of propeptide of type
I collagen (PICP) than homozygous AA (p=0.0459, Tukey´s test).
In FokI, BsmI and TaqI restriction sites the biochemical markers
of bone remodeling did not differ by genotype. In addition, no
significant difference was observed in VDR genotypic
distribution between osteoporotic women and non-osteoporotic
controls in the study group. To conclude, the FokI genotype of
the vitamin D receptor gene is related to bone mass at the hip
in Czech postmenopausal women, whereas the importance of
remaining VDR genotypes was not evident.
Key
words
Vitamin D receptor gene · FokI polymorphism · Bone mineral
density · Bone remodeling · Postmenopausal women
Reprint
requests
K.Zajíčková, Institute of Endocrinology, Národní 8, Prague 1,
116 94, Czech Republic, fax: 420-2-24905325, e-mail:
katka2222@volny.cz
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