PRNP and Alzheimer disease: Despite some degree of controversy regarding this receptor function and its relevance in AD (Balducci et al., 2010; Benilova and De Strooper, 2010; Calella et al., 2010; Kessels et al., 2010), binding of pathogenic oligomers to the flexible N-terminus of PrPC is thought to initiate a cascade of events that mediates their neurotoxicity and results in synaptic degeneration and neuronal loss (Resenberger et al., 2011; Larson et al., 2012; Um et al., 2012).