Improved clinical diagnostic criteria9 and assessment of the “spectrum” of FTLD10 present new opportunities to understand the determinants of poor survival, whether for disorders associated with primary tauopathies (PSP, CBS, nonfluent variant PPA, and half of bvFTD) or TDP-43 (TAR DNA-binding protein 43) pathologies (svPPA and half of bvFTD). This evidence concerns the gene TARDBP and behavioral variant of frontotemporal dementia.