Classifier 3 uniquely contains up-regulated gene sets implicated in ALS biology, including ‘synaptic vesicle priming’[35] (containing ALS risk locus UNC13A[35]), as well as ‘glutamine catabolic process’ and ‘activation of AMPA [glutamate] receptors’, which is likely related to glutamate excitotoxicity in ALS[35,37]. The gene discussed is UNC13A; the disease is amyotrophic lateral sclerosis.