APP and early-onset autosomal dominant Alzheimer disease: Alzheimer’s disease and dementias are in the top-ten ranking leading cause of death globally.8 Deposition of the insoluble and phosphorylated β-amyloid peptide (derived from amyloid precursor protein) in the brain parenchyma of Alzheimer’s disease patients affects functions/regeneration of various forms of neurons.9 The resulting widespread neuron damage affects synaptic communication leading to cognitive deficits, regional brain shrinkage, and brain atrophy;10 Huntington’s disease could appear in childhood or adolescence.