CACNA1H and Romano-Ward syndrome: The loci identified herein showed considerable overlap with those identified in a single similar study (25% locus overlap encompassing 38% of SUID cases herein).25 Recurrent loci were TTN-dilated cardiomyopathy 1G (5.3% of 356 total SUID cases), TSC1-tuberous sclerosis (1.7% of all cases), RYR2-catecholaminergic polymorphic ventricular tachycardia (2.0%), DSP-dilated cardiomyopathy (1.7% total cases), NOTCH1-Adams-Oliver syndrome 5 (1.4%), CACNA1H-familial hyperaldosteronism IV (1.4%), ANK2-Long QT syndrome 4 (1.4%), and FLNA-Melnick-Needles syndrome (1.1%)25.