APP and early-onset autosomal dominant Alzheimer disease: Alzheimer’s disease (AD) is the most common form of dementia affecting people aged 65 and older, which is characterized by two landmark pathologies, extracellular senile plaques consisting of amyloid-beta peptides (Aβ) and intracellular neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau proteins (Ulep et al., 2018).