Filaggrin mutations are genetic modifying factors exacerbating X-linked ichthyosis

J Invest Dermatol. 2007 Dec;127(12):2795-8. doi: 10.1038/sj.jid.5700971. Epub 2007 Jul 26.


Mutations inactivating the STS gene cause X-linked ichthyosis (XLI), whereas null mutations in the FLG gene cause ichthyosis vulgaris. Two brothers presented with XLI. One had a typical fine scaling, and the other was much more severely affected. Both patients carried STS missense mutation T165I. Furthermore, the more severely affected patient also carried heterozygous FLG mutation R501X, which was absent from his mildly affected brother. These data suggest that disrupting epidermal differentiation via different pathways can increase phenotypic severity. Owing to the high population frequency of FLG mutations, filaggrin is a possible genetic modifier in other genodermatoses.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Cell Differentiation
  • Child
  • Epidermis / metabolism
  • Family Health
  • Female
  • Humans
  • Ichthyosis, X-Linked / genetics*
  • Intermediate Filament Proteins / genetics*
  • Male
  • Models, Genetic
  • Molecular Sequence Data
  • Mutation*
  • Mutation, Missense
  • Phenotype


  • Intermediate Filament Proteins
  • filaggrin