To characterize the involvement of the PNS in tauopathies, we investigated tau pathology in cranial and spinal nerves (PNS-tau) in 54 tauopathy cases [progressive supranuclear palsy (PSP), n = 15; Alzheimer’s disease (AD), n = 18; chronic traumatic encephalopathy (CTE), n = 5; and corticobasal degeneration (CBD), n = 6; Pick’s disease, n = 9; limbic-predominant neuronal inclusion body 4-repeat tauopathy (LNT), n = 1] using immunohistochemistry, Gallyas silver staining, biochemistry, and seeding assays. This evidence concerns the gene MAPT and Alzheimer disease.