Firstly, although rare, pathologies other than FTLD or MND, such as corticobasal degeneration [13, 17], Alzheimer’s disease ([50–52], but see [44]), Parkinson’s disease [53] and Huntington disease-like conditions [9], have been associated with expansions in C9ORF72. Indeed, there has been one Belgian case with C9ORF72 expansion and clinical FTLD which lacks detectable TDP-43 pathology, but shows FTLD-UPS pathology [7]. This evidence concerns the gene TARDBP and Alzheimer disease.