APOE and early-onset autosomal dominant Alzheimer disease: APOE-ɛ4 positivity has been associated with accelerated seeding of amyloid pathology and an earlier onset of amyloid positivity.76,77 Furthermore, it has been suggested that the length of amyloid positivity correlates positively with the rate of the future progression of disease.77 Altogether, the results add to a growing body of literature suggesting that APOE contributes to the progression of Alzheimer’s disease both upstream and downstream of amyloidosis.