However,we note that even in the SCARB2 KO cells, thoughat lower levels, we still observe folded lysosomal GCase, which supportsthe proposal that GCase can indeed reach the lysosomeat leastin partthrough an M6P-independent process. In addition, the large number of genes linked to neurodegenerativediseases, especially PD, is striking and suggests that these may actupstream of GBA1 to influence lysosomal GCase activity.Our experiments with substrates for other lysosomal enzymes indicatethat such perturbations are generally not deleterious for the functionof lysosomal enzymes other than GCase. The gene discussed is SCARB2; the disease is Parkinson disease.