Numerous targeted therapies have been associated with HF, including anti-human epidermal growth factor receptor 2 (HER2) therapies, vascular endothelial growth factor (VEGF) signalling pathway inhibitors, rapidly accelerate fibrosarcoma B-type (BRAF), and mitogen-activated extracellular signal-regulated kinase (MEK) inhibitors and proteasome inhibitors (Table 1). The gene discussed is BRAF; the disease is hydrops fetalis.