As alluded to earlier, results of the present study also demonstrated that MITO fission-regulating proteins, namely Fis-1 and Drp-1, are markedly increased whereas fusion-regulating proteins, namely Mfn2, OPA-1, are markedly decreased in dogs with HF and human hearts with DCM or ICM etiology. This evidence concerns the gene OPA1 and familial dilated cardiomyopathy.