Estrogen receptor alpha polymorphism as a genetic marker for bone loss, vertebral fractures and susceptibility to estrogen.
OBJECTIVE
The purpose of the present study was to investigate the possible roles of PvuII and XbaI polymorphisms of the estrogen receptor alpha (ER(alpha)) in bone mineral density (BMD), vertebral fracture, bone loss rate after menopause and response to hormone replacement therapy (HRT).


METHODS
All 286 women were grouped according to the genotypes of PvuII or XbaI polymorphisms of the ER(alpha) gene. We compared the BMD Z-score, incidence of vertebral fracture, changes in Z-score after menopause and response of BMD to HRT among the genotypes.


RESULTS
Subjects with the PPxx genotype had significantly (P<0.05) lower Z-scores than did subjects with the other genotypes. A negative correlation was observed between the length of time after menopause and the decrease of the Z-score only in women with the pp genotype, suggesting faster bone loss in this group. In the analysis of the ER(alpha) polymorphism with regard to the effect of HRT on BMD, there appears to be a significantly greater increase of BMD (P<0.01 and 0.05) in women with the pp genotype than in those with the Pp or PP genotype.


CONCLUSIONS
PvuII and XbaI polymorphisms of the ER(alpha) gene were associated with BMD in postmenopausal Japanese women. Also, the polymorphisms may be useful genetic markers for predicting vertebral fracture in relatively young postmenopausal women. The PvuII polymorphism may be associated with susceptibility to changes in estrogen level.
Kobayashi
Noriko
N
Department of Obstetrics and Gynecology, Hokkaido University School of Medicine, Sapporo, Japan. fwhw3417@nifty.com
Fujino
Takafumi
T
Shirogane
Toru
T
Furuta
Itsuko
I
Kobamatsu
Yoko
Y
Yaegashi
Minoru
M
Sakuragi
Noriaki
N
Fujimoto
Seiichiro
S
D015502:Absorptiometry, Photon; D000328:Adult; D000368:Aged; D044466:Asian People / Q000235:genetics; D015519:Bone Density / Q000187:drug effects; D015252:Deoxyribonucleases, Type II Site-Specific / Q000235:genetics; D047628:Estrogen Receptor alpha; D015914:Estrogen Replacement Therapy; D005260:Female; D005819:Genetic Markers; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008159:Lumbar Vertebrae / Q000293:injuries; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000097:blood / Q000235:genetics*; D011110:Polymorphism, Genetic; D011960:Receptors, Estrogen / Q000097:blood / Q000235:genetics*; D016103:Spinal Fractures / Q000453:epidemiology*; D013131:Spine
D047628:Estrogen Receptor alpha; D005819:Genetic Markers; D011960:Receptors, Estrogen; C025580:endodeoxyribonuclease XBAI; C025630:CAGCTG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific