They have been detected near accumulation sites of the tau protein and beta-amyloid plaques in Alzheimer's disease (AD), near Lewy bodies in cases of dementia with Lewy bodies [18–20], and a state of intense microglial activation has been observed in mouse models of Parkinson's disease (PD) and human postmortem samples from PD patients [21, 22]. Here, MAPT is linked to Parkinson disease.