Hence, it is worthwhile to clarify in the future whether the reduction in circulating MOTS‐c levels in tumor patients is due to reduced secretion into the bloodstream due to low expression of MOTS‐c in tumor cells, or whether tumor patients as a whole have reduced levels of MOTS‐c expression, which opens up opportunity using circulating MOTS‐c as a non‐invasive means of predicting tumorigenesis or determining prognosis, which needs to be explored in larger clinical studies. The gene discussed is MT-RNR1; the disease is neoplasm.