Whereas homozygous or compound heterozygous mutations of GBA cause Gaucher disease, heterozygous GBA mutations increase the risk of developing PD and other synucleinopathies.54, 55GBA mutations are the most frequent genetic risk factor for PD identified to date, with 7% to 10% of PD patients carrying 1 of approximately 300 reported GBA mutations.54, 55. This evidence concerns the gene GBA1 and Gaucher disease.