RYR2 and cardiac arrhythmia: Recently, interictal arrhythmias was found in case 3 of BECTS identified with RYR2 c.8574G > A, and case 5 with compound heterozygous missense mutation (RYR2 c.7469T > C and c.12770G > A) presented sinus arrhythmia with mild cardiac structural abnormalities, and her father with no clinical symptoms, who carried a mutation (RYR2 c.12770G > A), also exhibited sinus arrhythmia (24).