C9orf72 and frontotemporal dementia: For example, although overexpression of the expansion results in robust RNA foci formation and c9RANT products accumulation (Wen et al., 2014; Molliex et al., 2015; Webster et al., 2016; Gendron et al., 2017), it does not result in reduced expression of c9orf72 mRNA and protein as seen in c9ALS/FTD patients (DeJesus-Hernandez et al., 2011; Renton et al., 2011).