title: Analysis of growth hormone receptor gene expression in tall and short stature children.
abstract: BACKGROUND
  The majority of children who present for evaluation of tall stature fall under the diagnosis of constitutional tall stature (CTS).
  
  
  METHODS
  To investigate mechanisms of tall stature, we evaluated serum IGF-I values and the expression of the GHR gene in the peripheral blood cells of 46 subjects with normal height, 38 with tall stature and 30 healthy children with short stature.
  
  
  RESULTS
  Our results showed significantly lower IGF-I levels in children with short stature (-0.57±0.18 SDS) compared to control children (0.056±0.19 SDS; p<0.0001) and to subjects with tall stature (0.594±0.17; p=0.00067). Furthermore, we found significantly higher GHR gene expression levels in tall children (321.84±90.04 agGHR/5×105agGAPDH) compared with other groups of subjects (short children: 30.13±7.5 agGHR/5×105agGAPDH, p<0.0001; controls: 86.81ag±19.5 GHR/5×105agGAPDH, p=0.035). The GHR gene expression level in short children was significantly lower compared with control subjects (p=0.0068).
  
  
  CONCLUSIONS
  Significantly higher GHR gene expression levels in tall subjects suggests a sensitization of the GHR-IGF system leading to overgrowth in CTS.
authors.affiliation: Department of Internal Medicine and Therapeutics, Unit of Pediatrics and Adolescentology, University of Pavia, Fondazione IRCCS San Matteo, Pavia.
authors.forename: Sara
authors.initials: S
authors.lastname: Pagani
authors.affiliation: Marienklinik, via Claudia De Medici 2, Bolzano.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Radetti
authors.affiliation: Department of Internal Medicine and Therapeutics, Unit of Pediatrics and Adolescentology, University of Pavia, Fondazione IRCCS San Matteo, Pavia.
authors.forename: Cristina
authors.initials: C
authors.lastname: Meazza
authors.affiliation: Department of Internal Medicine and Therapeutics, Unit of Pediatrics and Adolescentology, University of Pavia, Fondazione IRCCS San Matteo, Pavia.
authors.forename: Mauro
authors.initials: M
authors.lastname: Bozzola
mesh_terms: D001827:Body Height; D016022:Case-Control Studies; D002648:Child; D004392:Dwarfism / Q000097:blood* / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006130:Growth Disorders / Q000097:blood* / Q000473:pathology; D019382:Human Growth Hormone / Q000097:blood*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D011379:Prognosis; D011986:Receptors, Somatotropin / Q000097:blood*
chemical_list: D011986:Receptors, Somatotropin; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I
keywords: GHR gene; IGF-I; growth; growth hormone (GH); growth hormone-binding protein (GHBP); tall children