LRRK2 and Parkinson disease: Pathological examination of LRRK2-PD brains harboring the G2019S mutation has identified typical, transitional, and diffuse Lewy pathology, tau and neurofibrillary tangle pathology, TDP-43 aggregates, ubiquitin inclusions, and even “pure” neurodegeneration without overt pathology (Paisán-Ruıíz et al., 2004; Zimprich et al., 2004; Biskup and West, 2008; Wider et al., 2010; Ujiie et al., 2012; Ling et al., 2013).