Other than the three major LQTS causative genes, ten minor genes (AKAP9, CACNA1C, CALM1, CALM2, CAV3, KCNE1, KCNE2, KCNJ2, KCNJ5, SCN4B, SNTA1) and two atypical type of LQTS causative genes (ANK2 [8] and KCNJ2 [9]) have been discovered to date, all of which were tested for within this study [10, 11]. Here, CALM2 is linked to familial long QT syndrome.