While TGF-β has been shown in a number of studies to be involved in cardiac development and is essential for efficient differentiation of hPSCs to CMs (MacLellan et al., 1993; Camenisch et al., 2002; Watabe and Miyazono, 2009), elevated TGF-β signaling in the human heart is also associated with various pathological conditions, including hypertrophic cardiomyopathy (Dobaczewski et al., 2011). The gene discussed is TGFB1; the disease is hypertrophic cardiomyopathy.