TARDBP and frontotemporal dementia: TDP-43 pathology is associated with almost all cases of ALS/FTD characterised by a hexanucleotide GGGGCC (G4C2) repeat expansion in intron 1 of chromosome 9 open reading frame 72 (C9ORF72), the most common genetic cause of ALS and FTD (C9ALS/FTD) (DeJesus-Hernandez et al., 2011; Renton et al., 2011; Murray et al., 2011).