PTPA and Alzheimer disease: Notably, tau missense mutations found in frontotemporal dementia with Parkinsonism linked to chromosome 17 (FTDP-17; Goedert et al., 2000) and AD-mimicking tau phosphorylation in proline-rich motifs (Eidenmuller et al., 2001) inhibit the association of tau with PP2A (Figure 3B).