GBA1 and Parkinson disease: In research focusing on Parkinson’s disease and other synucleinopathies like dementia with Lewy Bodies (DLB), GBA1 D409V mutant mice exhibit drastically reduce GCase activity, accumulation of the GCase substrate glucosphingosine (GlcSph), accumulation of aSyn in the hippocampus, and learning and memory impairments [17, 18, 21, 26].