Neuropathology in AD is hallmarked by abnormal accumulation of amyloid beta peptide (Aβ), a highly neurotoxic derivative of the amyloid precursor protein (APP) which is a transmembrane protein that is particularly concentrated in synapses (Haass and Selkoe, 2007; Masters and Selkoe, 2012; Mucke and Selkoe, 2012; Hampel et al., 2021). Here, APP is linked to Alzheimer disease.