PSEN2 and Alzheimer disease: We used the transgenic construct APP695 isoform (APP695ΔNL) that bears the Swedish mutation for AD (KM670/671NL), and enhances the overall production of Aβ [71–73] (Supplementary Figure 2C) for co-expression with the mutant PSEN1 constructs in PSEN1-/-/PSEN2-/-MEF cells.