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]. This evidence concerns the gene SCN4B and familial long QT syndrome.