These changes are similar to the changes in hearts of cardiomyocyte-specific ErbB2 receptor17, 18 and ErbB4 receptor knockout mice19 and of the patients with trastuzumab-induced20 cardiomyopathy, suggesting that ErbB signaling might be involved in the cardiac phenotype of Bmx/CA mice. The gene discussed is EGFR; the disease is cardiomyopathy.