SN lesions are frequently present in AD and include pigmented neuronal cell loss, gliosis, Lewy bodies, α-synuclein-stained structures, and hyperphosphorylated tau accumulation in neurofibrillary tangles as well as neuritis (Kazee et al., 1995; Klunk et al., 2004; Burns et al., 2005), suggesting that AD is a significant risk factor for SN lesions (Kazee et al., 1995; Kazee and Han, 1995). The gene discussed is MAPT; the disease is Alzheimer disease.