Houge G, Oeffner F, Grzeschik KH.
Haukeland University Hospital, Bergen, Norway.
Eur J Hum Genet 2008;16:1027–8.
Editor’s note: This letter to the
European Journal of Human Genetics suggests that X-linked dominant angioma serpiginosum is allelic with Gorlin–Goltz syndrome or Focal Dermal Hypoplasia (FDH). It describes a three-generation family that not only had angioma serpiginosum, i.e. vascular streaks along Blaschko’s lines, but unusually also had mild nail dystrophy and esophageal papillomatosis. Clinically, these findings overlap slightly with FDH, although features such as eye, skeletal, or other malformations were not present. In this family, the authors identified partial deletions of chromosome Xin an area containing the
PORCN or porcupine gene, a regulator of Wnt signaling, which has recently been shown to be deleted or mutated in FDH (
Nat Genet 2007;39:833–5,
Nat Genet 2007;39:836–8). The deletion of Xp11.23 identified encompasses
PORCN and four other genes and is only slightly smaller than a deletion previously described to cause FDH (
Nat Genet 2007;39:833–5) The authors have no clear explanation for the phenotypic difference in these conditions, but suggest differences in X inactivation (lyonisation) or the presence of modifying genes.