Increased ROS production in CMs causes the activation of members of the MAPK pathway, extracellular signal regulated kinase 1 and 2 (ERK1/2) and JNKs, and the members of the TGF-β superfamily, all of which promote myocardial hypertrophy (Zhang et al., 2003; Dobaczewski et al., 2011; Bjornstad et al., 2012). The gene discussed is MAPK3; the disease is cardiac hypertrophy.