Previously a relatively little-studied protein, the stature of TDP-43 has grown considerably due to description of mutations in the TARDBP gene in sporadic and familial cases of ALS and the discovery that TDP-43 is a major constituent of ubiquitin-positive inclusions in FTD and ALS (Neumann et al., 2006; Sreedharan et al., 2008). Here, TARDBP is linked to frontotemporal dementia.