Sjögren-Larsson Syndrome - Diagnostic Tests

Diagnostic Tests

Histology: Histology is rather non-specific displaying striking hyperkeratosis, papillomatosis, acanthosis and slight upper-dermal inflammation.

Histochemical staining for FAO: Histochemical staining for FAO can be performed on routine histology slides and is an indirect measurement of FALDH activity. It reveals a reduction in FAO dependent formazan deposits in the lower epidermis and adnexal structures in comparison to normal skin.

FALDH-activity assay: This is them most reliable assay for diagnosing SLS and is performed on cultured fibroblast, keratinocytes, or lymphocytes. Using a longchain aldehyde as substrate the fatty aldehyde-dependent production of NADH is measured fluorometrically. Alternatively, a gas chromatography-mass spectrometry assays can be used.

Diagnostic Tools

This section offers to professional users instruments helpful to establish the disease diagnosis. Specific entries include:

  1. model questionnaires, protocols, or checklists, which may guide clinicians and laboratory personnel in the diagnostic procedure of specific disease groups/subgroups;
  2. a list of cell biology/biochemical tools used for laboratory diagnosis of specific diseases or group of diseases;
  3. a list of molecular genetics tools, including mutational screening procedures, oligonucleotide primer sequences, PCR amplification conditions, and other details for selected diseases. In this section, you also find the link for the gene-specific page of the Weizmann Institute of Science GeneCards website ( which is an integrated database including information on disease relationships, SNPs, gene expression, gene function and more.
  4. a mutation database with a GENESKIN updated list of the mutations identified in the genes responsible for selected diseases. A link with the gene-specific page at the Human Gene Mutation Database maintained at the University of Wales in Cardiff ( and other databases, such as the collagen database in Leicester (, is also available.

Model Questionnaire

Here you will find the downloadable version of the ichthyosis patient form. This document is currently used to collect patient details before sending the biological sample to the diagnostic laboratory, in order to ease cellular and/or molecular investigations.

Ichthyosis patient form

Molecular Genetic Tools

Causative gene(s)

ALDH3A2 Genecards Logo

Mutation Database

Causative gene(s)