There is increasing evidence that other neurodegenerative diseases, most notably Alzheimer’s disease (Aβ and tau), Parkinson’s disease (α‐synuclein), frontotemporal dementia (TDP43, tau or FUS) and motor neurone disease (TDP43), exhibit at least some of the misfolded prion protein properties. This evidence concerns the gene MAPT and early-onset autosomal dominant Alzheimer disease.