The distribution of two different vitamin D receptor polymorphisms (BsmI and start codon) in primary hyperparathyroidism.
BACKGROUND
The bb genotype of the BsmI polymorphism of the vitamin D receptor (VDR) is more common in primary hyperparathyroidism (HPT) than in the general population in Swedish and German women. However, little is known about the association of HPT with the start codon polymorphism of the VDR (defined by FokI).


OBJECTIVE
To study the distribution of the VDR genotypes in a group of women with HPT compared with a control group. The bone mineral density (BMD) of different genotypes was also investigated.


METHODS
VDR alleles were typed by polymerase chain reaction (PCR) assay around the polymorphic BsmI or FokI restriction sites in 67 control women (48.5 +/- 10 years) and 53 women with HPT (61.4 +/- 11 years). They were all Caucasian and born in the Canary Islands. Lumbar and proximal femur BMDs were measured by dual X-ray absorptiometry (DXA) and quantitative computed tomography (QCT).


RESULTS
The 'bb' genotype was equally frequent in controls and HPT subjects (46.3 and 45.3%, respectively). There was a trend towards a lower prevalence of the FF genotype amongst women with HPT as compared with controls (41.5 vs. 57.1%; P = 0.09). BMD was lower in patients with HPT compared with controls in the lumbar spine and the proximal femur.


CONCLUSIONS
The association of the BsmI polymorphism of the VDR gene with HPT is not applicable to all geographical areas. In Canarian postmenopausal women suffering from HPT, VDR genotype distribution is similar to that found in controls. A possible association of HPT with the FokI polymorphism deserves further investigation.
Sosa
M
M
Department of Medicine, University Hospital Insular, Bone Metabolic Unit, University of Las Palmas de Gran Canaria, Las Palmas, Canary Islands, Spain. msosa@cicei.ulpgc.es
Torres
A
A
Martín
N
N
Salido
E
E
Limiñana
J M
JM
Barrios
Y
Y
De Miguel
E
E
Betancor
P
P
D000368:Aged; D000483:Alleles; D015519:Bone Density; D016022:Case-Control Studies; D017931:DNA Primers; D015252:Deoxyribonucleases, Type II Site-Specific / Q000235:genetics*; D005260:Female; D005838:Genotype; D005858:Germany; D006801:Humans; D006961:Hyperparathyroidism / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D016017:Odds Ratio; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D017698:Postmenopause; D018167:Receptors, Calcitriol / Q000235:genetics*; D013548:Sweden
D017931:DNA Primers; D018167:Receptors, Calcitriol; C035042:endodeoxyribonuclease FokI; D015252:Deoxyribonucleases, Type II Site-Specific