It has been demonstrated that upregulation of GCase activity by a small molecule GCase modulator S-181 in induced pluripotent stem cells (iPSC)-derived dopaminergic neurons can ameliorate α-synuclein accumulation, lipid substrate accumulation, dopamine oxidation and lysosomal dysfunction in both GBA1-linked and non-GBA1-linked PD cases. This evidence concerns the gene GBA1 and Parkinson disease.