Because a wealth of data from genetic studies has demonstrated that transcriptional control of Scn5a and Kcnh2 is critical for conduction, repolarization, and arrhythmia susceptibility in humans,91,92 the finding that the GR exerts temporal regulation over these genes through binding sites conserved in humans and mice (evolutionary distance=90 million years) is of particular translational relevance. This evidence concerns the gene KCNH2 and cardiac arrhythmia.