It was previously reported that APP or APP fragments accumulated in dystrophic neurites in AD brains (Ishii et al., 1989) and that the accumulation of APP and its metabolic fragments induced neurotoxicity and vesicular trafficking impairment (Yoshikawa et al., 1992; Kametani et al., 2004; Roy et al., 2005). The gene discussed is APP; the disease is Alzheimer disease.