The aim of the study described here was to assess the predictive accuracy of five in silico programs (SIFT, PolyPhen-2, PROVEAN, SNPs&GO and SNAP), alone or in combination, and two metaservers (Meta-SNP and PredictSNP) in evaluating SNVs in the three major LQTS genes (KCNQ1, KCNH2 and SCN5A). This evidence concerns the gene KCNH2 and familial long QT syndrome.