Περίληψη:
It is well established that genetic factors play a major role in the
pathogenesis of osteoporosis. Previous reports have suggested that
vitamin D receptor (VDR) gene polymorphisms, particularly the BE, tt and
AA genotypes, are associated with low bone mineral density (BMD). If
these VDR genotypes are indeed an important determinant of BMD, then a
population of related osteoporotic individuals (mother-daughter or
sister-sister relationship) should have a high prevalence of the BE, tt
or AA VDR genotypes. To test this hypothesis we determined the VDR
genotypes in 26 osteoporotic persons (age 44.3 +/- 12.7 years, mean +/-
SD) belonging to 12 families. Furthermore, for comparison with existing
studies, we applied the VDR genotype analysis in a population of 53
unrelated healthy subjects (age 45.2 +/- 9.8 years, mean +/- SD) and 59
unrelated osteoporotic subjects (age 52.1 +/- 9.0 years, mean +/- SD).
The menopausal status of the healthy and osteoporotic populations was
pre-, peri- and mostly early postmenopausal. The proportions of the
three genotypes, BE, tt and AA, within the 12 osteoporotic families were
15%, 12% and 27%, respectively, whereas the proportions of the other
three homozygous genotypes (bb, TT, aa) were 50%, 50% and 23%. The
distribution of the BE, tt and AA genotypes in the normal population was
21%, 21% and 36%, respectively (vs bb, TT, aa: 36%, 38%, 21%),
whereas in the osteoporotic population it was 23%, 20% and 34% (vs
bb, TT, aa: 27%, 34%, 14%). Our data indicate that there is not a
statistically significant (p>0.05) difference in the VDR genotype
frequencies within osteoporotic families as compared with the same
genotypes in the population of unrelated normal or osteoporotic
subjects. VDR genotype analysis showed no significant relation between
VDR polymorphisms and BMD or Z-score values at the lumbar spine. This
study demonstrates the lack of a heritability pattern between the BE, tt
and PLA genotypes and low BMD.
Συγγραφείς:
Fountas, L
Moutsatsou, P
Kastanias, I
Tamouridis, N and
Tzanela, M
Anapliotou, M
Sekeris, CE