FUS and proteostasis deficiencies: Among the 1,495 cases with FTLD where data were available, the underlying proteinopathy was identified as tauopathy in 567 cases (37.93%), TAR DNA-binding protein 43 (TDP-43) proteinopathy in 248 cases (16.59%), and Fused in Sarcoma (FUS) pathology in 8 cases (0.54%; Table 4).