title: Prediction of bone mineral density from vitamin D receptor polymorphisms is uncertain in representative samples of Japanese Women. The Japanese Population-based Osteoporosis (JPOS) Study.
abstract: BACKGROUND
  Vitamin D receptor (VDR) gene polymorphisms have been inconsistently associated with bone mineral density (BMD). To precisely evaluate the associations between three VDR gene polymorphisms and BMD, we performed a large-scale representative study of the Japanese female population.
  
  
  METHODS
  Fifty women were randomly selected from each of the 5-year age stratified populations (15-79 years) in each of the three municipalities examined, as a part of the Japanese population-based osteoporosis (JPOS) baseline study in 1996. In the study, BMD at the lumbar spine, hip, and distal forearm were measured using dual energy X-ray absorptiometry (DXA). Two polymorphisms were determined in the VDR gene locus identified by the restriction endonucleases ApaI and TaqI through a novel allele discrimination method using two different allele-specific fluorescence probes. The other VDR gene polymorphism was identified by the restriction endonuclease FokI using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Changes in BMD were determined in a follow-up study 3 years after the baseline study.
  
  
  RESULTS
  After the exclusion of women who had any medical or menstrual history affecting BMD, 1434 women were analysed. The annual per cent changes in BMD at the lumbar spine over 3 years in subjects with tt genotype in the TaqI polymorphism were different from other genotypes, both in the women who were premenopausal at the follow-up survey (F-premenopausal women) and in the women who were postmenopausal at the baseline survey (B-postmenopausal women). However, the effects of tt genotype on change in BMD were opposite in the two groups. In addition, these associations or tendencies were not observed at the different skeletal sites.
  
  
  CONCLUSIONS
  This study revealed that none of the individual VDR gene polymorphisms displayed consistent association with baseline BMD or BMD change. Therefore, the effect of the VDR genotype on bone mass is negligible in Japanese women.
authors.affiliation: Department of Public Health, Kinki University School of Medicine 377-2 Ohno-Higashi, Osaka-Sayama, Osaka 589-8511, Japan. akemi@med.kindai.ac.jp
authors.forename: Akemi
authors.initials: A
authors.lastname: Morita
authors.forename: Masayuki
authors.initials: M
authors.lastname: Iki
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Dohi
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Ikeda
authors.forename: Sadanobu
authors.initials: S
authors.lastname: Kagamimori
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Kagawa
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Matsuzaki
authors.forename: Hideo
authors.initials: H
authors.lastname: Yoneshima
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Marumo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000886:Anthropometry; D015519:Bone Density / Q000235:genetics*; D005260:Female; D005500:Follow-Up Studies; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000208:ethnology / Q000235:genetics*; D011110:Polymorphism, Genetic; D017698:Postmenopause / Q000235:genetics / Q000502:physiology; D017697:Premenopause / Q000235:genetics / Q000502:physiology; D018167:Receptors, Calcitriol / Q000235:genetics*
chemical_list: D018167:Receptors, Calcitriol