Similarly to Parkinson’s disease where α-synuclein forms aggregates, Alzheimer’s disease neuropathology is characterized by deposits of extracellular amyloid-β (Aβ) peptide and intraneuronal neurofibrillary changes of hyper-phosphorylated protein tau (Braak and Braak, 1991; Tiraboschi et al., 2004). The gene discussed is MAPT; the disease is early-onset autosomal dominant Alzheimer disease.