Alzheimer's disease is characterized by the progressive aggregation of amyloid β-42 and hyperphosphorylated tau leading to the generation of neurofibrillary tangles, inflammation, and alterations in neurotrophic factors such as BDNF within the brain which ultimately resulted in neuronal damage, particularly in the cholinergic system [30]. The gene discussed is MAPT; the disease is early-onset autosomal dominant Alzheimer disease.