C9orf72 and amyotrophic lateral sclerosis: Evidence also exists that C9orf72 mutation carriers have an increased prevalence of certain autoimmune disorders (O'Rourke et al, 2016), increased microglial pathology (Brettschneider et al, 2012), and increased thinning in frontal and temporal lobes in neuroimaging studies, compared to sporadic ALS and controls (Floeter et al, 2016).