Of note, heterozygous LoF variants in the related KCNH2 gene (HERG), originally identified for their involvement in cardiac arrhythmia [6,7], may also be related to epilepsy [8,9,10], including one variant which causes an A561V amino acid substitution in Kv11.1 [11,12], homologous to the recently reported A371V amino acid substitution in Kv12.2. This evidence concerns the gene KCNH2 and cardiac arrhythmia.