A growing body of evidence in humans and experimental models suggests that corin, a cardiac transmembrane II serine protease, plays diagnostic, prognostic, and protective roles in DCM and HFrEF development [9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24]. The gene discussed is CORIN; the disease is familial dilated cardiomyopathy.