Studies have shown that obesity is associated with a decrease in circulating and adipose tissue expression levels of FGF21 and Irisin as well as their specific receptors, β‐Klotho and FGFR1 for FGF21 and ITGA5 for Irisin, respectively.7, 8, 9, 10, 11. The gene discussed is FNDC5; the disease is obesity due to melanocortin 4 receptor deficiency.