C9 and amyotrophic lateral sclerosis: Both expanded repeat‐containing transcripts (sense and antisense) can be translated into poly‐dipeptides (dipeptide repeat [DPR] proteins) which accumulate in MNs of C9‐ALS patients (Figure 1c; Freibaum & Taylor, 2017; Gendron et al., 2017; Mori, et al., 2013; Saberi et al., 2018; Wen et al., 2014; Zu et al., 2013).