Targeting circulating concentrations of irisin has been recently suggested to hold tremendous promise for treatment of metabolic disease since in irisin-treated normal or diet-induced type 2 diabetes mice, the activity of beige fat was selectively increased leading to suppressed weight gain, enhanced fatty acid oxidation, and improved glucose metabolism [14, 16, 18]. The gene discussed is FNDC5; the disease is type 2 diabetes mellitus.