The findings of various independent studies indicate that the expression level of C9orf72 transcripts is reduced in C9FTD/ALS patients (DeJesus-Hernandez et al., 2011; Gijselinck et al., 2012; Belzil et al., 2013a; Fratta et al., 2013). Here, C9orf72 is linked to amyotrophic lateral sclerosis.