Given this common cause of sALS with FTD, 10% of sALS and an additional 10% of FTD, the next question, given that it has taken more than 25 years with SOD1 mutations, is just how cytotoxicity occurs with the GGGGCC (G4C2) HRE within the C9ORF72 gene? The gene discussed is C9orf72; the disease is frontotemporal dementia.