Most "sporadic" cases of X-linked ichthyosis are not de novo mutations

Acta Derm Venereol. 1999 Mar;79(2):143-4. doi: 10.1080/000155599750011381.


X-linked ichthyosis is an inherited disease with dark, regular and adherent scales as clinical characteristics. It is caused by a deficiency of the steroid sulphatase enzyme. Steroid sulphatase assay is a relative easy tool that enables correct diagnosis of X-linked ichthyosis patients and carriers. A large number of X-linked ichthyosis patients correspond to non-familial cases that seem to represent de novo mutations. In this study, we examined the X-linked ichthyosis carrier state of the mothers of 42 non-familial cases to determine whether their children corresponded to de novo mutations. To classify patients and carriers, a steroid sulphatase assay was performed in leukocytes using 7-[3H]-dehydroepiandrosterone sulphate as substrate. In 36 mothers (85%) we found steroid sulphatase activity compatible with the carrier state of X-linked ichthyosis. This data suggest that most of the mothers of these patients present the primary gene defect, excluding de novo mutations in the patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arylsulfatases / blood*
  • Arylsulfatases / deficiency
  • Arylsulfatases / genetics
  • Female
  • Humans
  • Ichthyosis, X-Linked / diagnosis*
  • Ichthyosis, X-Linked / enzymology
  • Ichthyosis, X-Linked / genetics*
  • Male
  • Mutation*
  • Pedigree
  • Steryl-Sulfatase


  • Arylsulfatases
  • Steryl-Sulfatase