C9orf72 and frontotemporal dementia: Indeed, elongating polyribosomes have been shown to stall on GGGGCC (G4C2) repeat expansion in the C9orf72 gene, known to cause FTD and ALS (C9-ALS/FTD), leading to the production of neurodegeneration-driving dipeptide repeat proteins through repeat-associated non-AUG (RAN) translation and to translation inhibition [40].