We further demonstrated that measurements from prion disease blood of not only T-Tau, but both P-Tau and T-Tau and calculation of the P-Tau/T-Tau ratio may be useful for discriminating patients with CJD from individuals with other neurodegenerative disorders based on our observation that P-Tau in sCJD is unchanged, whereas it is elevated in AD [30]. This evidence concerns the gene MAPT and Alzheimer disease.