C9orf72 and frontotemporal dementia: Likewise, arginine-rich dipeptide repeats (R-DPRs, poly-GR and poly-PR) that are generated via repeat-associated non-ATG (RAN) translation from a disease-causing intronic hexanucleotide repeat expansion in the C9orf72 locus in C9ALS/FTD [77], can also engage diverse NIRs [41, 78, 79].