In addition to Aβ and tau aggregates, 30–70% of AD patients also display intracellular α-syn accumulation (Lippa et al., 1998; Hamilton, 2000; Marui et al., 2000; Rosenberg et al., 2000; Arai et al., 2001; Jellinger, 2003; Parkkinen et al., 2003; Popescu et al., 2004; Ol et al., 2006; Uchikado et al., 2006). The gene discussed is MAPT; the disease is Alzheimer disease.