This can now be tested clinically by “re-purposing” the specific β3-AR agonist, mirabegron that was developed and approved in Europe, USA and Japan for the treatment of overactive bladder disease, where the drug improves bladder filling by activating β3-AR in the detrusor muscle leading to myorelaxant effects [90]. The gene discussed is ADRB3; the disease is overactive bladder.