CACNA1C and familial long QT syndrome: For our CRISPR-Cas9 experiments, we focused on two known mutations in the CACNA1C gene: c.2570C>G or p.(Pro857Arg), corresponding to c.2607C>G or p.(Pro871Arg) in zebrafish, associated with a long QT syndrome (LQTS) phenotype19 and c.989C>T or p.(Thr330Met), corresponding to c.1028C>T or p.(Thr343Met) in zebrafish, associated with Brugada syndrome (BrS)20.