Moreover, multiple familial gene mutations such as Presenilin-1 (PSEN1) and Amyloid Precursor Protein (APP) that trigger AD are characterized by elevated lysosome pH which compromises autolysosome function and leads to the accumulation of toxic protein aggregates, such as amyloid-beta (Aβ) [162]. The gene discussed is PSEN1; the disease is Alzheimer disease.