In comparison, a previous investigation into synaptic changes in the prefrontal cortex of ALS patients revealed no differences in synaptic loss between SOD1 and C9orf72 associated cases, but did suggest that synaptic loss was most significant in cases displaying TDP-43 pathology—of which SOD1 cases showed none [38]. The gene discussed is TARDBP; the disease is amyotrophic lateral sclerosis.