MAPT and Alzheimer disease: Alzheimer’s disease (AD) is a neurodegenerative disease that is characterised by neuropathological accumulation of amyloid-beta (Aβ) plaques (A), intraneuronal tau neurofibrillary tangles (T), and neurodegeneration (N) in the brain (Braak and Braak, 1991; Serrano-Pozo et al., 2011).