MAPT and early-onset autosomal dominant Alzheimer disease: Accumulation of Tau protein in PSP predominantly involves isoforms containing 4 microtubule-binding domain repeats and lacking N-terminal insertions (0N/4R-Tau)6,7 (this contrasts with Alzheimer’s disease and chronic traumatic encephalopathy, in which multiple 3R- and 4R-Tau isoforms are deposited).