Besides the documented effects of Aβ deposition around cerebral blood vessels (BVs), recent evidence indicates that tau pathology induces CVD (21–23), and that the presence of hippocampal perivascular tau strictly correlates with blood brain barrier (BBB) permeability and loss of integrity (24), prompting new questions to elucidate the molecular mechanisms through which tau toxicity affects the cerebral vasculature, in both AD and other tauopathies. This evidence concerns the gene MAPT and Alzheimer disease.