TDP-43 is a predominantly nuclear protein, but was first linked to ALS and FTD as the main protein found in the ubiquitin-positive cytoplasmic inclusions in the neurons, including motor neurons, of ALS and of FTD patients, with a clearance of its usual nuclear localization (Arai et al., 2006; Neumann et al., 2006). This evidence concerns the gene TARDBP and frontotemporal dementia.