title: Fatal outcome in a female monozygotic twin with X-linked hypohydrotic ectodermal dysplasia (XLHED) due to a de novo t(X;9) translocation with probable disruption of the EDA gene.
abstract: Ectodermal dysplasias are a group of congenital disorders with defective development of the epidermis and its appendages. X-linked hypohydrotic ectodermal dysplasia (XLHED; OMIM 305100) is the most common form of ectodermal dysplasia. We report on two monozygotic twin girls with XLHED due to a t(X;9) translocation causing a disruption of the EDA gene and non random inactivation of the normal X chromosome. One of the girls died unexpectedly at 2.5 years of age. Autopsy revealed that lack of normal tracheobronchial secretions leading to complete tracheal obstruction by mucous debris was the probable cause of death.
  
  
  CONCLUSIONS
  Morbidity and mortality of ectodermal dysplasias in infancy and early childhood can be significant. Early diagnosis by paediatricians is important and complications should be anticipated.
authors.affiliation: Division autonome de Génétique Médicale, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland. zankl@medgen.unizh.ch
authors.forename: A
authors.initials: A
authors.lastname: Zankl
authors.forename: M C
authors.initials: MC
authors.lastname: Addor
authors.forename: P
authors.initials: P
authors.lastname: Cousin
authors.forename: A C
authors.initials: AC
authors.lastname: Gaide
authors.forename: F
authors.initials: F
authors.lastname: Gudinchet
authors.forename: D F
authors.initials: DF
authors.lastname: Schorderet
mesh_terms: D002675:Child, Preschool; D004476:Ectodermal Dysplasia / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology; D017809:Fatal Outcome; D005260:Female; D008040:Genetic Linkage; D006801:Humans; D007007:Hypohidrosis; D007223:Infant; D007231:Infant, Newborn; D014178:Translocation, Genetic; D014430:Twins, Monozygotic; D014960:X Chromosome / Q000235:genetics*