MAPT and Alzheimer disease: While the indirect properties such as the size and protease resistance of tau aggregates and cellular or neuropathology patterns in the reporter HEK293 cells and transgenic mice [149], and posttranslational modifications (PTMs) of tau in mass spectrometry [8,147] suggested similar structure of tau in individual AD cases, the new direct biophysical and conformational data revealed evolving conformer populations driving in prion-like manner different phenotypes in individual AD [10] cases (Figure 3).