MAPT and Alzheimer disease: The ALS/PDC brain, like that of other tauopathies (AD, PSP, FTD linked to chromosome 17, Corticobasal Degeneration, Pick disease, Niemann Pick disease type C), shows markers of cell-cycle reactivation in neurons with tau pathology destined for degeneration (Husseman et al., 2000; Wang et al., 2009; Stone et al., 2011).