In the breast cancer population there are standard systemic anti-cancer therapies used which are accepted to carry a risk of cardiac dysfunction, or cardiovascular toxicity; namely anthracyclines, immune checkpoint inhibitors, taxanes, fluoropyrimidines, cyclophosphamide, carboplatin, HER2-specific tyrosine kinase inhibitors, and nucleoside analogues [20], [21], [22], [23], [24], [25], [26], [27]. The gene discussed is ERBB2; the disease is cancer.