We designed the tau368 mice here to express hTau 1–368 since it showed relatively higher cytotoxicity than many other tau fragments [25], while it is also possible for the hTau1-368 fragment to be further cleaved by murine AEP or other endogenous enzymes to generate smaller-size and toxic tau species, like what happens in human AD brains. This evidence concerns the gene MAPT and Alzheimer disease.