In particular, the amino-terminals of trypsin-resistant tau in AD, in which both 3R tau and 4R tau isoforms are deposited, are clearly distinct from those in 3R tauopathy PiD or 4R tauopathies CBD, PSP and FTDP-17T (intron +13/16) (Figure 3). Here, MAPT is linked to tauopathy.