MAPT and argyrophilic grain disease: Diseases with an accumulation of tau aggregates are termed tauopathies and include AD, progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17), argyrophilic grain disease (AGD), aging-related tau astrogliopathy (ARTAG) and primary age-related tauopathy (PART; Arendt et al., 2016).