Together, these data point to a primary function for RNF20 during cardiogenesis in cardiomyocyte development (Fig. 1A, Figs S3 and S4) that results in defective compact myocardium and deficient ventricular septum, which is consistent with some of the structural CHD observed in humans with variants affecting H2Bub1-deposition complex components. The gene discussed is RNF20; the disease is coronary artery disorder.