RYR2 and Arrhythmia: Thus, RyR1 mutations are linked to skeletal muscle disorders including malignant hyperthermia and central core disease, while RyR2 mutations have a direct causative role in the heart rhythm disorders catecholaminergic polymorphic ventricular tachycardia (CPVT) and arrhythmogenic right ventricular dysplasia (ARVD), and discrete RyR2 mutations have also been recently implicated in dilated cardiomyopathy (DCM) (Haas et al., 2014).