Aggregations of 4R-tau are pathologic hallmarks of corticobasal degeneration (CBD), progressive supranuclear palsy (PSP), argyrophilic grain dementia (AGD), globular glial tauopathy (GGT), aging-related tau astrogliopathy (ARTAG), and microtubule-associated protein tau (MAPT) gene mutation-associated familial frontotemporal dementia (FTD) and parkinsonism, whereas neuronal inclusions of 3R-tau are characteristic of Pick’s disease (PiD) [17, 19, 21]. The gene discussed is MAPT; the disease is frontotemporal dementia.