Identification of differentially expressed genes (DEGs) co-existing in the nerve tissue, lymphoid tissue, and whole blood of amyotrophic lateral sclerosis (ALS) patients and their functional enrichment analysis. (A) Venn diagram of the up-regulated genes in the nerve tissue, lymphoid tissue, and whole blood (G2: DEGs in nerve tissue of ALS patients (sel.2g), L: DEGs in lymphoid tissue of ALS patients, S: DEGs in whole blood of ALS patients). (B) Venn diagram of the down-regulated genes in the nerve tissue, lymphoid tissue, and whole blood of ALS patients. Gene Ontology (GO) biological process analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of the (C,D) up- and (E,F) down-regulated genes co-existing in the nerve tissue and lymphoid tissue of ALS patients and the (G,H) up-regulated genes co-existing in the nerve tissue and whole blood of ALS patients.