There are more than a thousand genes that affect the mitochondria, and many that may be altered within the biochemical pathways of mitochondrial disease. In this study, Sapient analyzed samples from over 100 individuals from a rare disease population with sequence-verified mitochondrial disease and found there are specific small molecules that are altered in these patients. In fact, a set of chemically-related biomarkers were found which represent a new biochemical pathway not yet described before in humans.