C9 and amyotrophic lateral sclerosis: To investigate the synaptic proteome of the ALS spinal cord, we collected post-mortem samples from a total of 30 donors: 10 fALS patients carrying C9orf72 repeat expansion (C9 + ve), 10 sporadic (sALS) with TDP-43 pathology and 10 age- and gender-matched healthy individuals.