First, when α-secretase mutations that co-segregate with late-onset AD are introduced into tg2576 AD model mice harboring APP Swedish mutation, anti-amyloidogenic α-cleavage of APP is shown to be reduced, with Aβ increased presumably by the enhancement of amyloidogenic β-cleavage (Suh et al., 2013). The gene discussed is APP; the disease is Alzheimer disease.