GBA1 and Parkinson disease: Based on the assumption that a decrease in GCase activity might favor alpha-synuclein accumulation and synucleinopathy development, AAV- mediated GBA1 delivery has been tested in mouse models of GD-related PD to assess its effects on GCase and alpha-synuclein modulation (Sardi et al., 2011, 2013; Rocha et al., 2015b).