In the cardiovascular system, elevated levels of p300 are associated with cardiac hypertrophy, cardiomyopathy, fibrosis, heart failure, and pathologies of cardiac aging (Bugyei‐Twum et al., 2014; Rai et al., 2019; Sunagawa et al., 2011; Wei et al., 2008). Here, EP300 is linked to cardiac hypertrophy.