Molecular autopsies of SUDEP cases suggest some decedents carry mutations and potentially pathogenic variants in genes associated with cardiac arrhythmias such as KCNQ1 as well as genes associated with severe epilepsies such as SCN1A and DEPDC5.11,12,30,36 However, these variants occur in a minority of SUDEP cases and additional genetic determinants of SUDEP risk likely exist but remain elusive due to the relatively low frequency of SUDEP, heterogenous mechanisms of seizure-related death, and potentially diverse genetic factors. The gene discussed is SCN1A; the disease is cardiac arrhythmia.