Yang Long et al. [19] proposed that activatingtransforming growth factor-β1 (TGF-β1)/c-Jun N-terminal kinase (JNK)–mitogen-activated protein kinase (MAPK) and extracellular regulated protein kinases (ERK)–MAPK signaling pathways might be implicated in developing atrial fibrillation secondary to valvular heart disease. The gene discussed is TGFB1; the disease is heart valve disorder.