MAPT and early-onset autosomal dominant Alzheimer disease: In the course of progression of Alzheimer disease, intraneuronal neurofibrillary tangles, composed of P-tau, accumulate sequentially in various regions of the brain, starting from entorhinal and peripheral cortex, then expanding to the hippocampus (especially the CA1 region) and the limbic regions, further to amygdala, thalamus, claustrum, the isocortical areas, and finishing in primary sensory, motor, and visual nexuses (for a recent review, see Carroll et al. 2021).