Apart from AD and CTE, 3R + 4R tau filaments are found in several other tauopathies, including primary age–related tauopathy (52), familial British and Danish dementias (25), some prion protein amyloidoses (53), frontotemporal dementias caused by missense mutations V337M and R406W in MAPT (54), subacute sclerosing panencephalitis, amyotrophic lateral sclerosis/Parkinsonism–dementia complex of Guam and the Kii peninsula (55), and in vacuolar tauopathy (56). Here, MAPT is linked to frontotemporal dementia.