APOE and early-onset autosomal dominant Alzheimer disease: Moreover, NPC patients carrying Apolipoprotein E (APOE) ε4 alleles develop extracellular cerebral deposition of β-amyloid (Aβ) peptides [6], a characteristic pathological feature of Alzheimer’s disease (AD), the most common type of senile dementia affecting the elderly [7], [8], [9], [10].