title: Vitamin D receptor polymorphism among rickets children in Mongolia.
abstract: BACKGROUND
  It was reported that 32% of children under five years old in Mongolia had symptoms of rickets. Vitamin D receptor (VDR) gene polymorphism has received attention in relation to bone metabolism. We therefore investigated whether VDR polymorphism is related to high prevalence of rickets in Mongolia and to bone properties in childhood.
  
  
  METHODS
  We conducted a case-control study in Ulaanbaatar involving 80 children aged 7-10 years with a history of rickets (cases) and 72 children with no history of rickets (controls). VDR polymorphism was assessed using BsmI, ApaI, and TaqI, and bone properties were determined by measuring age standardized tibial cortical speed of sound (TCSOS).
  
  
  RESULTS
  Each allelic frequency was verified to satisfy the Hardy-Weinberg equilibrium in cases, controls, and the total sample. The VDR polymorphisms among cases (BB 3%, Bb 18%, bb 80%; AA 15%, Aa 38%, aa 47%; and TT 81%, Tt 17%, tt 3%) did not differ significantly from those among controls (BB 1%, Bb 13%, bb 86%; AA 16%, Aa 46%, aa 38%; and TT 86%, Tt 13%, tt 1%). There were no significant differences in TCSOS according to the VDR genotype among either cases or controls.
  
  
  CONCLUSIONS
  The VDR polymorphism does not play a major role in the development of rickets in Mongolia and has no effect on TCSOS in childhood.
authors.affiliation: Health Promotion, Division of Public Health, Graduate School of Tokyo Medical and Dental University, Yushima, Tokyo, Japan.
authors.forename: Akie
authors.initials: A
authors.lastname: Kaneko
authors.forename: Vaanchig
authors.initials: V
authors.lastname: Urnaa
authors.forename: Keiko
authors.initials: K
authors.lastname: Nakamura
authors.forename: Masashi
authors.initials: M
authors.lastname: Kizuki
authors.forename: Kaoruko
authors.initials: K
authors.lastname: Seino
authors.forename: Tomoko
authors.initials: T
authors.lastname: Inose
authors.forename: Takehito
authors.initials: T
authors.lastname: Takano
mesh_terms: D015519:Bone Density; D016022:Case-Control Studies; D002648:Child; D005838:Genotype; D006306:Health Surveys; D006801:Humans; D008986:Mongolia / Q000453:epidemiology; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D015995:Prevalence; D018167:Receptors, Calcitriol / Q000235:genetics*; D012279:Rickets / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D013977:Tibia / Q000000981:diagnostic imaging; D014463:Ultrasonography
chemical_list: D018167:Receptors, Calcitriol