Interestingly, previous studies had reported that β-arrestin1 (Liu et al, 2013) and β-arrestin2 (Thathiah et al, 2013) are significantly increased in brains of AD patients and that both β-arrestin1 and β-arrestin2 interact with the Aph-1 subunit of the γ-secretase complex to increase Aβ production, thereby linking β-arrestin1 and β-arrestin2 to Aβ pathogenesis. Here, APH1A is linked to Alzheimer disease.