TARDBP and torsades de pointes: Immunoblotting of sarkosyl-insoluble urea-soluble fractions extracted from FTLD-TDP brains define a disease-specific signature for TDP-43 including a high molecular weight smear, phosphorylated full-length TDP-43 with a molecular mass size of 45–50 and 60 kDa, and truncated forms at 24–26 kDa, identified as C-terminal fragments of TDP-43 (Fig. 3) [6, 47].