MAPT and proteostasis deficiencies: FTD clinical phenotypes with underlying FTLD-Tau and FTLD-TDP are clinically similar and there is no diagnostic marker available to reliably predict the underlying neuropathology antemortem. Moreover, there are no current FDA-approved therapies, although emerging therapeutic strategies that target protein-specific mechanisms necessitate accurate antemortem diagnosis and differentiation of FTLD-Tau and FTLD-TDP proteinopathy groups [4].