The brains of patients with AD are characterized by the deposition of extracellular amyloid plaques consisting of β-amyloid (Aβ) peptides, the product of the proteolytic processing of the amyloid precursor protein (APP), and by abnormal hyperphosphorylation of the Tau protein, which precipitates in the form of neurofibrillary tangles inside the neurons48,49. The gene discussed is APP; the disease is Alzheimer disease.