GBA1 and Parkinson disease: Compared to sporadic PD patients without GBA mutation (PDGBA_wild type), PDGBA present with a higher prevalence of cognitive impairment and more frequently suffer from additional non-motor symptoms including neuropsychiatric disturbances (depression, anxiety, hallucination), autonomic dysfunction, and sleep disturbances such as REM-sleep-behavior disorder (RBD) (Brockmann et al., 2011; Barrett et al., 2014).