NOTCH3 and Alzheimer disease: Many other NOTCH3 variants have been associated with CADASIL that typically replace the wild-type amino acid with a cysteine residue or replace a highly conserved cysteine residue with another amino acid,20,26,27 although there are several exceptions.43 Available clinical and autopsy data for the individuals with NOTCH3 mutations were consistent with the diagnosis of AD and not CADASIL.