Larger clinical studies are needed to elucidate the relationship between circulating inflammatory markers and irisin in children with T2DM, as well as experimental studies to elucidate the mechanisms of hypoirisinemia in T2DM, as irisin may ultimately play a role as a therapeutic agent in obesity and in T2DM. This evidence concerns the gene FNDC5 and obesity due to melanocortin 4 receptor deficiency.