Because several other high- or moderate-impact NOTCH3 mutations have been associated with cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a diagnostically distinct disorder marked by severe headaches in young adulthood followed by strokes and dementia later in life,20 we sought clinical and autopsy data from the participants with AD with the rs149307620 mutation to determine whether they are enriched for cerebrovascular risk factors. Here, NOTCH3 is linked to Alzheimer disease.