SOD1 and amyotrophic lateral sclerosis: To investigate transcriptional regulatory mechanisms which might associate ATF3 with SOD1-mutant ALS patients any further, we integrated H3K27me3 repressive histone marks identified during ChIP-seq data analysis (specifically for SOD1-mutant patients) with significantly suppressed genes detected in the expression data of the public repository (SOD1 n = 3; HC n = 3)17.