Enzymatic diagnosis of Sjögren-Larsson syndrome using electrospray ionization mass spectrometry.
BACKGROUND
Sjögren-Larsson syndrome is a metabolic disorder characterized by accumulation of long-chain fatty alcohols in plasma of patients due to mutations in the ALDH3A2 gene, that codes for a microsomal fatty aldehyde dehydrogenase (FALDH). Recent studies have demonstrated that FALDH is involved in the last step of the conversion of 22-hydroxy-C22:0 into the dicarboxylic acid of C22:0 (C22:0-DCA).


METHODS
FALDH activity was determined by incubating fibroblast homogenates with omega-hydroxy-C22:0 in the presence of NAD(+). Electrospray ionization mass spectrometry (ESI-MS) was used to quantify the amounts of C22:0-DCA produced.


RESULTS
All SLS patients were deficient in C22:0-DCA productions with activities ranging from 3.2-26.3% of mean control.


CONCLUSIONS
The new assay described in this paper has substantial advantages over previous assays, and allows for the easy, reliable and rapid diagnosis of SLS.
Sanders
Robert-Jan
RJ
Department of Genetic Metabolic Diseases, University of Amsterdam, Academic Medical Center, Amsterdam, The Netherlands.
Ofman
Rob
R
Dekker
Conny
C
Kemp
Stephan
S
Wanders
Ronald J A
RJ
D000445:Aldehyde Oxidoreductases / Q000235:genetics*; D006801:Humans; D016111:Sjogren-Larsson Syndrome / Q000175:diagnosis* / Q000201:enzymology / Q000235:genetics; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D000445:Aldehyde Oxidoreductases; C038828:long-chain-aldehyde dehydrogenase