MAPT and early-onset autosomal dominant Alzheimer disease: Alzheimer’s disease is a neurodegenerative disorder manifested by extracellular amyloid beta plaques in the grey matter, intraneuronal hyperphosphorylated tau filaments, neuronal death, synapse elimination, and brain atrophy, and is associated with free radical and oxidative stress, metabolic dysregulation, and upregulated pro-inflammatory cytokines [153].