Due to the critical role of IKs in heart rhythm regulation, unsurprisingly, many mutations in KCNQ1 and KCNEs have been functionally linked to life-threatening long and short QT syndromes as well as atrial fibrillation (Wang et al., 1996; Chen Y. H. et al., 2003; Moss and Kass, 2005; Olesen et al., 2014; Steffensen et al., 2015; Peng et al., 2017). This evidence concerns the gene KCNQ1 and atrial fibrillation.