C9orf72 and amyotrophic lateral sclerosis: Increasingly, these neuroimaging modalities are being linked to understanding the molecular pathology of ALS, such as the degree of deeper cortical structures and cerebellar pathology evident in those ALS patients carrying pathological hexanucleotide expansions in C9orf72, even in the presymptomatic stages (Mahoney et al., 2012; Bede et al., 2013; Rohrer et al., 2015; Walhout et al., 2015).