SLC4A3 and Familial short QT syndrome: Twenty of them were associated with a definite phenotype of SQTS: five in the KCNH2 gene, four in the KCNJ2 gene, six in the KCNQ1 gene and five in SLC4A3. The four remaining variants were located in the KCNH2 gene, but were associated with a phenotype of Brugada Syndrome (BrS) with a shorter than normal QT interval (stnQT).