NDUFA6 and amyotrophic lateral sclerosis: Among the genes that were notably down-regulated (NDUFA4, COX5B, COX6C, NDUFA3, NDUFB4, COX5A, COX6A2, NDUFA6, COX8A and ATP5MC1), only NDUFA4 has been previously identified in connection with ALS.