title: Prepubertal girls with Turner syndrome and children with isolated SHOX deficiency have similar bone geometry at the radius.
abstract: BACKGROUND
  The low bone mineral density (BMD) and alterations in bone geometry observed in patients with Turner syndrome (TS) are likely caused by hypergonadotropic hypogonadism and/or by haploinsufficiency of the SHOX gene.
  
  
  OBJECTIVE
  Our objective was to compare BMD, bone geometry, and strength at the radius between prepubertal girls with TS and children with isolated SHOX deficiency (SHOX-D) to test the hypothesis that the TS radial bone phenotype may be caused by SHOX-D.
  
  
  METHODS
  This comparative cross-sectional study was performed between March 2008 and May 2011 in 5 large centers for pediatric endocrinology.
  
  
  METHODS
  Twenty-two girls with TS (mean age 10.3 years) and 10 children with SHOX-D (mean age 10.3 years) were assessed using peripheral quantitative computed tomography of the forearm.
  
  
  RESULTS
  BMD, bone geometry, and strength at 4% and 65% sites of the radius were evaluated.
  
  
  RESULTS
  Trabecular BMD was normal in TS (mean Z-score = -0.2 ± 1.1, P = .5) as well as SHOX-D patients (mean Z-score = 0.5 ± 1.5, P = .3). At the proximal radius, we observed increased total bone area (Z-scores = 0.9 ± 1.5, P = .013, and 1.5 ± 1.4, P = .001, for TS and SHOX-D patients, respectively) and thin cortex (Z-scores = -0.7 ± 1.2, P = 0.013, and -2.0 ± 1.2, P < .001, respectively) in both groups. Bone strength index was normal in TS as well as SHOX-D patients (Z-scores = 0.3 ± 1.0, P = .2, and 0.1 ± 1.3, P = .8, respectively).
  
  
  CONCLUSIONS
  The similar bone geometry changes of the radius in TS and SHOX-D patients support the hypothesis that loss of 1 copy of SHOX is responsible for the radial bone phenotype associated with TS.
authors.affiliation: Department of Pediatrics, Second Faculty ofMedicine, Charles University in Prague and University Hospital Motol, 15006 Prague 5, Czech Republic. ondrej.soucek@lfmotol.cuni.cz
authors.forename: O
authors.initials: O
authors.lastname: Soucek
authors.forename: J
authors.initials: J
authors.lastname: Zapletalova
authors.forename: D
authors.initials: D
authors.lastname: Zemkova
authors.forename: M
authors.initials: M
authors.lastname: Snajderova
authors.forename: D
authors.initials: D
authors.lastname: Novotna
authors.forename: K
authors.initials: K
authors.lastname: Hirschfeldova
authors.forename: I
authors.initials: I
authors.lastname: Plasilova
authors.forename: S
authors.initials: S
authors.lastname: Kolouskova
authors.forename: M
authors.initials: M
authors.lastname: Rocek
authors.forename: Z
authors.initials: Z
authors.lastname: Hlavka
authors.forename: J
authors.initials: J
authors.lastname: Lebl
authors.forename: Z
authors.initials: Z
authors.lastname: Sumnik
mesh_terms: D000293:Adolescent; D015519:Bone Density; D001846:Bone Development; D001848:Bone Diseases, Developmental / Q000209:etiology*; D001842:Bone and Bones / Q000737:chemistry / Q000473:pathology*; D002648:Child; D002657:Child Development; D003430:Cross-Sectional Studies; D018153:Czech Republic; D005260:Female; D056726:Genetic Association Studies; D030342:Genetic Diseases, Inborn / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D006130:Growth Disorders / Q000209:etiology; D057895:Haploinsufficiency; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008297:Male; D055595:Mechanical Phenomena; D009154:Mutation; D011884:Radius; D012729:Sex Chromosome Aberrations; D000074122:Short Stature Homeobox Protein; D014424:Turner Syndrome / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*
chemical_list: D018398:Homeodomain Proteins; C106071:SHOX protein, human; D000074122:Short Stature Homeobox Protein