Due to recent developments in cryogenic electron microscopy(cryo-EM) measurements, the structures for many fibrils have now beensolved which were elusive earlier.10−13 Thus, the structures for taufibrils from AD, CTE, and PiD patients have become available recently.10,11,13 The first report of a tau fibrilstructure from an AD brain (will be referred to as AD-tau) was demonstratedby Fitzpatrick et al. in 2017 which showed a double C-type structure(where the outer C filament surrounds the inner filament). The gene discussed is MAPT; the disease is Alzheimer disease.