Previously we reported specific neuropathological differences between FAD and early onset SAD, with increased 6E10 positive Aβ levels in the frontal cortex and cerebellum of PS1 E280A FAD cases (Sepulveda-Falla et al., 2011), and some Aβ morphological differences in another subset of PS1 E280A patients (Trujillo-Rodríguez et al., 2014). Here, PSEN1 is linked to familial Alzheimer disease.