C9orf72 and frontotemporal dementia: Specifically, C9ORF72-related ALS-FTD neuropathology is characterized by the formation of nuclear RNA foci containing the expanded C9ORF72 transcript (DeJesus-Hernandez et al. 2011; Renton et al. 2011) as well as prominent deposition of neomorphic polydipeptide repeats (poly-PR, poly-GR, poly-PA, poly-GP, and poly-GA) that arise from unconventional repeat-associated non-AUG (RAN) translation of the expanded C9ORF72 transcript in multiple reading frames.