Unexpected phenotype in a boy with trisomy of the SHOX gene

J Pediatr Endocrinol Metab. 2010 Jan-Feb;23(1-2):159-69. doi: 10.1515/jpem.2010.23.1-2.159.

Abstract

The assessment that heterozygous SHOX mutations leading to SHOX haploinsufficiency play a role in patients with idiopathic short stature (ISS) is already documented in the literature as well as the suggestion that additional copies of SHOX are strongly implicated in a condition of tall stature. However, we report the first case of short stature in a male associated with the presence of three copies of the SHOX gene. Through chromosomal analysis, using Multiplex Ligation-dependent Probe Amplification method of SHOX salsa P018B kit and microsatellite analysis, we identify a new interstitial isolated duplication of the SHOX gene and its enhancer caused by a larger duplication of the PAR1 region in a boy with ISS. Consequently, we propose the hypothesis that this chromosome re-arrangement disrupts the regular interaction between the enhancer and promoter, resulting in a transcription block, thus producing a lack of gene activation, causing the clinical feature of short stature.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Base Sequence
  • Body Height
  • Bone Development / genetics
  • Enhancer Elements, Genetic / genetics
  • Gene Dosage / genetics
  • Growth Disorders / diagnostic imaging
  • Growth Disorders / genetics*
  • Homeodomain Proteins / genetics*
  • Humans
  • Male
  • Molecular Sequence Data
  • Phenotype
  • Promoter Regions, Genetic / genetics
  • Radiography
  • Short Stature Homeobox Protein
  • Trisomy / genetics*

Substances

  • Homeodomain Proteins
  • SHOX protein, human
  • Short Stature Homeobox Protein