GBA1 and Parkinsonism: Patients with type-1 GD, the most common form of GD, frequently develop parkinsonism.38 Heterozygous carriers of GBA1 mutations are at a higher risk for PD.39, 40 It has been shown that about 75% of Lewy bodies, a pathological hallmark of PD, colocalized with GCase 1 in brains of PD and DLB patients with heterozygous GBA1 mutations.41 These results suggest that lysosomal enzyme deficiency is associated with the development of PD.