Hexanucleotide Repeat Induced Nuclear Export and Translation of Circular Intronic RNA in C9ORF72-ALS/FTD

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are currently incurable diseases caused by motor neuron degeneration. The most common cause of inheritable ALS and FTD is an expansion of hexanucleotide GGGGCC repeat in the C9ORF72 gene. RNA containing the abnormally long GGGGCC repeats may form RNA foci that sequester essential RNA binding proteins. Alternatively, RNA containing repeats can be exported from nucleus and translated via repeat associated non-AUG (RAN) translation to generate different toxic poly dipeptide repeats (DPR).