More specifically, it was suggested that lysosomal GCase and alpha-synuclein are linked in a bidirectional pathogenic loop in synucleinopathies as shown in cell cultures and in induced-pluripotent stem (IPS) cell-derived dopaminergic midbrain neurons: (1) Functional loss of GCase activity compromises lysosomal degradation of alpha-synuclein and causes its aggregation due to reduced lysosomal chaperone-mediated autophagy. Here, SNCA is linked to synucleinopathy.