Within the “amyloidolytic” pathway, soluble forms of Aβ are cleaved by BACE1 into non-toxic and non-aggregating Aβ34 which we previously discovered as an indicator of amyloid clearance in amyloid-positive individuals with mild cognitive impairment who later progressed to dementia (10, 11, 14). The gene discussed is BACE1; the disease is dementia.