FUS and frontotemporal dementia: The presence of fibrillar TDP-43 in neuronal inclusions is a hallmark of nearly all forms of ALS-FTD (Neumann et al. 2006), with the exception of disease caused by mutations in SOD1 or FUS, which result in inclusions that are TDP-43-negative but positive for SOD1 or FUS, respectively (Rosen et al. 1993; Kwiatkowski et al. 2009; Vance et al. 2009).