title: Focal dermal hypoplasia in a male patient due to mosaicism for a novel PORCN single nucleotide deletion.
abstract: BACKGROUND
  Focal dermal hypoplasia (FDH) is an X-linked dominant disorder caused by nonsense mutations and deletions in the PORCN gene coding for a transmembrane endoplasmic reticulum protein required for Wingless signalling. Symptoms consist mainly of linear atrophic skin defects, skeletal deformities and, in many cases, mental retardation. Osteopathia striata is a nearly constant feature. Approximately 90% of patients are women. A few instances of father-to-daughter transmission and a number of sporadic male cases presumably as a result of somatic mosaicism have been recorded.
  
  
  OBJECTIVE
  The aim of this study was to demonstrate the presence of somatic mosaicism for PORCN mutations in a male patient.
  
  
  METHODS
  We sequenced the PORCN gene in different tissues from a boy with symptoms of FDH.
  
  
  RESULTS
  We demonstrate post-zygotic mosaicism for a novel deletion in the PORCN gene.
  
  
  CONCLUSIONS
  A novel PORCN deletion, present in a post-zygotic mosaic, causes focal dermal hyplasia in a male patient.
authors.affiliation: Department of Clinical Genetics Dermatology, Maastricht University Medical Center, Maastricht, the Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Vreeburg
authors.forename: M
authors.initials: M
authors.lastname: van Geel
authors.forename: L G T
authors.initials: LG
authors.lastname: van den Heuij
authors.forename: P M
authors.initials: PM
authors.lastname: Steijlen
authors.forename: M A M
authors.initials: MA
authors.lastname: van Steensel
mesh_terms: D000217:Acyltransferases; D002675:Child, Preschool; D005489:Focal Dermal Hypoplasia / Q000235:genetics*; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D009030:Mosaicism; D017384:Sequence Deletion / Q000235:genetics*
chemical_list: D008565:Membrane Proteins; D000217:Acyltransferases; C491188:PORCN protein, human