MAPT and Alzheimer disease: Alzheimer’s disease (AD) is a complex neurological disorder, the aetiology of which is associated with clinical hallmarks, such as a decline in neurotransmitter acetylcholine (ACh) levels, amyloid-β (Aβ) peptide deposits, oxidative stress, dyshomeostasis of biometals, and tau protein hyperphosphorylation and accumulation [1,2,3].