C9orf72 and frontotemporal dementia: Interestingly, a strong interplay between three FTD-ALS-associated genes, C9orf72, TBK1, and TARDBP, was recently found: TBK1 is phosphorylated in response to C9orf72 poly(gly-ala) aggregation and sequestered into inclusions, resulting in decreased TBK1 activity and contributing to neurodegeneration.