The p.R328C variant was first reported by Chevalier et al. (2001) in an acquired LQTS cohort.47 Grunnet et al. (2005) described a cLQTS patient harbouring double mutations (KCNQ1:pR591H; KCNH2:p.R328C). This evidence concerns the gene KCNQ1 and familial long QT syndrome.