Approximately, 5–30% of PD patients carry GBA1 mutations; variations in the prevalence rate of GBA1 mutations can be attributed to the population studied and extent of exome sequencing (Sidransky et al. 2009; Duran et al. 2013; Schapira 2015; Cilia et al. 2016, Senkevich and Gan-Or 2020). Here, GBA1 is linked to Parkinson disease.