PSEN1 and Alzheimer disease: In the present study, mice overexpressing neuron-specific transgenes with five familial AD (5×FAD) mutations, namely Florida (I716V), Swedish (K670N and M671L), and London (V717I) in human amyloid precursor protein (APP) and M146L and L286V in human presenilin 1 (PS1) [12], were used as a model of AD.