Relation of vitamin D receptor FokI start codon polymorphism to bone mineral density and occurrence of osteoporosis in postmenopausal women in Taiwan.
BACKGROUND
Osteoporosis is a common disorder with a strong genetic component. Our aim was to evaluate the correlation of the vitamin D receptor FokI start codon polymorphism to bone mineral density and the occurence of osteoporosis.


METHODS
We determined the vitamin D receptor FokI start codon polymorphism using polymerase chain reaction-based restriction analysis in 163 postmenopausal women in Taiwan. The vitamin D receptor gene polymorphism was detected by the restriction enzyme FokI, where the F allele indicated the absence of the cuttable site and the f allele its presence. We then related the genotypes to bone mineral density and the occurence of osteoporosis in these women.


RESULTS
The allelic frequencies for 163 postmenopausal women in Taiwan were 59.2% for F and 40.8% for f in FokI restriction fragment length polymorphisms. The prevalence of each genotype in the study population was: 42.3% FF, 33.7% Ff and 24% ff. The three genotypic groups differed significantly in bone mineral density at the lumbar spine (P = 0.029). Bone mineral density was highest in the Ff group and lowest in the ff group at the lumbar spine and the femoral neck. The FokI vitamin D receptor genotype showed a significant effect on the prevalence of osteoporosis in the subjects at the lumbar spine. That is, women with genotype ff had a 2.8 times greater risk for osteoporosis (P < 0.05), and those with genotype FF had a 0.8 times greater risk than women with genotype Ff.


CONCLUSIONS
Our findings indicate that the vitamin D receptor FokI start codon polymorphism is associated with reduced bone mineral density and predisposes women to osteoporosis at the lumbar spine.
Chen
Huey-Yi
HY
Department of Obstetric and Gynecology, China Medical College Hospital, School of Medicine, China Medical College, Taichung, Taiwan.
Chen
Wen-Chi
WC
Hsu
Cheng-Der
CD
Tsai
Fuu-Jen
FJ
Tsai
Chang-Hai
CH
D000483:Alleles; D001483:Base Sequence; D015519:Bone Density / Q000235:genetics*; D018387:Codon, Initiator; D015331:Cohort Studies; D016001:Confidence Intervals; D003720:Densitometry; D015252:Deoxyribonucleases, Type II Site-Specific / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008875:Middle Aged; D008969:Molecular Sequence Data; D016017:Odds Ratio; D015663:Osteoporosis, Postmenopausal / Q000453:epidemiology / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D015995:Prevalence; D011336:Probability; D018167:Receptors, Calcitriol / Q000235:genetics*; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D013624:Taiwan / Q000453:epidemiology
D018387:Codon, Initiator; D018167:Receptors, Calcitriol; C035042:endodeoxyribonuclease FokI; D015252:Deoxyribonucleases, Type II Site-Specific