FUS and amyotrophic lateral sclerosis: To further explore the impact of gene expression levels on FUS-ALS phenotypes (FUS mutant and WT controls), we used the GSEA algorithm to investigate the relationship between gene expression in the combined dataset and the biological processes, cellular components, molecular functions and KEGG pathways involved (p ≤ 0.05) (Supplementary Table S3, Figure 3E, Supplementary Figures S1 and S2).