Abstract: Neurodegenerative diseases that affect the motor neurons, including amyotrophic lateral sclerosis (ALS), have little treatment options and are generally rapidly fatal (1, 2). We harnessed the power of unbiased, whole transcriptome differential gene expression analysis, utilizing primary patient cells and tissues to discover genes whose expression defines ALS using published data (3, 4). We found significant differential expression of CIART, encoding circadian associated repressor of transcription, in the skeletal muscle of patients with ALS. CIART was also differentially expressed in the induced pluripotent stem cell (iPSC)-derived motor neurons of patients with ALS. CIART transcript was present at significantly lower levels in ALS patient skeletal muscle as compared to control skeletal muscle. These analyses will begin to define the transcriptional landscape of ALS.