Association of the calcitonin gene (CA) polymorphism with bone mass and bone responsiveness to hormone therapy in postmenopausal Korean women.
OBJECTIVE
To evaluate the relationship between cytosine-adenine (CA) polymorphism of the calcitonin gene, serum calcitonin levels, bone mineral density (BMD) and bone responsiveness to hormone therapy (HT).


METHODS
Calcitonin (CA) polymorphism, serum calcitonin, and BMD at the lumbar spine and proximal femur were determined in 430 postmenopausal Korean women. In all, 181 women were treated with sequential HT for 2 years.


RESULTS
Four major calcitonin alleles were present with a frequency greater than 5%: 122 base pair (bp) 61.3%, 108 bp 25.1%, 110 bp 7.0%, and 124 bp 6.2%. There were no differences in the BMD at the lumbar spine and proximal femur in postmenopausal women with zero, one, or two copies of major alleles. Serum calcitonin levels in women with two copies of the 108 bp allele were significantly higher than those in women with zero or one copy of the 108 bp allele. The annual rate of positive change of BMD at the femoral neck after HT was significantly higher in women homozygous for the 108 bp allele than in women with zero or one copy of the 108 bp allele, but the number of copies of the major calcitonin alleles was not significantly associated with HT-responsiveness.


CONCLUSIONS
The calcitonin (CA) polymorphism is one of the genetic factors that may affect BMD changes at the femoral neck after HT in Korean women.
Kim
Jung Gu
JG
Department of Obstetrics & Gynecology, Seoul National University Hospital, 28 Yeungun-Dong Chongno-Ku, Seoul 110-744, Korea. kimjg@plaza.snu.ac.kr
Choi
Young Min
YM
Moon
Shin Yong
SY
Lee
Jin Yong
JY
D015519:Bone Density / Q000187:drug effects* / Q000235:genetics; D002116:Calcitonin / Q000097:blood / Q000235:genetics*; D003094:Collagen / Q000097:blood; D024042:Collagen Type I; D018900:Dinucleotide Repeats / Q000235:genetics; D015914:Estrogen Replacement Therapy; D004966:Estrogens, Conjugated (USP) / Q000008:administration & dosage; D005260:Female; D005269:Femur / Q000187:drug effects; D005272:Femur Neck / Q000187:drug effects; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D007723:Korea; D008159:Lumbar Vertebrae / Q000187:drug effects; D017258:Medroxyprogesterone Acetate / Q000008:administration & dosage; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy* / Q000235:genetics; D010455:Peptides / Q000097:blood; D011110:Polymorphism, Genetic
D024042:Collagen Type I; D004966:Estrogens, Conjugated (USP); D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D002116:Calcitonin; D003094:Collagen; D017258:Medroxyprogesterone Acetate