Glycosphingolipid (GSL) lysosomal degradative pathway. The sequential removal of glycosidic residues from the ceramide backbone of GSLs by specific lysosomal enzymes is shown. Glucosylceramide is the penultimate GSL in this pathway and the enzyme acid β-glucosidase has defective function in Gaucher disease. Each of the other enzyme deficiencies in this pathway are associated with specific LSDs (eg, α-galactosidase A in Fabry disease).