KCNN3 and atrial fibrillation: In 2010, the KCNN3 gene, encoding a calcium-gated potassium channel involved in atrial repolarization, was identified as the third AF-associated locus in a lone AF population by Ellinor et al. Two years later, the first GWAS meta-analysis from the international Atrial Fibrillation Genetics (AFGen) Consortium, including ~6,500 AF cases, revealed six new genetic loci for AF (28).