GBA1 and Parkinson disease: Overall, it has been estimated that some GBA1 mutations may increase 20- to 30-fold the PD risk (Spitz et al., 2008; Sidransky et al., 2009; Bultron et al., 2010; McNeill et al., 2012; Mao et al., 2013; Blanz and Saftig, 2016; Migdalska-Richards and Schapira, 2016; Aflaki et al., 2017; O’Regan et al., 2017; Standaert, 2017).