GBA1 and Parkinson disease: GD is caused by mutations in the glucocerebrosidase (GBA) gene and is associated with PD as it appears that similar underlying defects in autophagy and mitochondrial dysfunction may link the neurodegenerative aspect of these two disorders (Tayebi et al., 2001; Sun and Grabowski, 2010; Westbroek et al., 2011; Osellame et al., 2013).