KCNH2 and atrioventricular block: Interestingly, Bezzerides and colleagues9 showed that SGK1 inhibition by SGK1 Morpholino knockdown or injection with SGK1-dominant negative messenger RNA can rescue the 2:1 atrioventricular block phenotype manifestation of prolonged APD in the zebrafish breakdance mutant (bkd–/–) that is due to a mutation in the zebrafish homologue of the KCNH2 gene and recapitulates the human LQT2 phenotype.9