DAD-mediated triggered arrhythmias are underlined by Ca2+ handling instability in AF, namely RyR dysfunction (increased phosphorylation and open probability), increased SERCA function, increased diastolic SR Ca2+ leak and spontaneous SR Ca2+ release, increase in Ca2+ sparks and waves, enhanced CaMKII function (with subsequent RyR hyperphosphorylation), or reduced ICa,L (Sood et al., 2008; Neef et al., 2010; Shan et al., 2012; Voigt et al., 2012). The gene discussed is RYR2; the disease is atrial fibrillation.