As discussed earlier [insert hyperlink: disease overview], Fabry disease leads to accumulation of GL-3 predominately in the lysosomes of several cell types. The level of GL-3 is routinely measured in blood and urine (occasionally biopsy) samples, and the clearance of GL-3 from various cell types and tissues has been evaluated as an endpoint in clinical studies for ERTs and further has been utilized as a biomarker (usually using plasma or urine GL-3 measurement) in the monitoring of Fabry disease patients.

Recently, lyso-GL-3 has emerged as a more sensitive biomarker that may correlate with disease severity and/or organ involvement in Fabry disease. Lyso-GL-3, also known as globotriaosylsphingosine, is a deacylated form of GL-3. Aerts J et al Biomarkers in the diagnosis of lysosomal storage disorders: proteins, lipids, and inhibodies. J Inherit Metab Dis.<br /> Smid BE, et al. Plasma globotriaosylsphingosine in relation to phenotypes of Fabry disease. J Med Genet. 2015 Apr;52(4):262-8.