GAB2 and early-onset autosomal dominant Alzheimer disease: Indeed, p97/Gab2 is required for the PI3K/AKT1 signaling pathway [49] and p97/Gab2-mediated PI3K/AKT1 activation is involved in the pathogenesis of Alzheimer’s disease (AD) [50] that shows the reduced GRIA1 surface expression [51].