Tam et al. analyzed the transcriptomes of 148 ALS cortical tissue samples and identified three ALS transcriptomic clusters marked by (1) oxidative and proteotoxic stress (61%), (2) glial activation (19%), and (3) high levels of retrotransposon expression and signatures of TARDBP/TDP-43 dysfunction (20%) [123]. Here, TARDBP is linked to amyotrophic lateral sclerosis.