To determine whether r‐irisin can prevent the development of the characteristic changes of type I DCM, we used mice that were treated with r‐irisin to counteract the effects of DCM before the disease model was already established, and we used two doses of irisin (0.5 and 1.5 μg/g body weight/day) and continued the experiment for 8 weeks. The gene discussed is FNDC5; the disease is familial dilated cardiomyopathy.