MAPT and Alzheimer disease: The main pathological features of AD include massive loss of cholinergic neurons and their synapses in cerebral cortex and hippocampus, vascular amyloidosis in cortical arteries and arterioles, accumulation of amyloid β-amyloid protein (Aβ), and abnormal hyperphosphorylation of tau protein to form neurofibrillary tangles [6].