RYR2 and cardiac arrhythmia: Mutations in RYR2 have been well-known in the etiology of arrhythmogenic disorders,31 while more recent studies reported that the same mutation can cause GGE independent of arrhythmias.32,33 Our finding adds weight to the hypothesis that RYR2 mutations likely constitute a neuro-cardiac calcium channelopathy,32,33 where mutant receptors may induce either arrhythmias or GGE depending on their selective expression in the heart or in the brain.