Moreover, given the interest of the human potassium channel hERG as a source of acquired LQTS, most of the studies carried out on the zebrafish heart aimed to test the potential cardiotoxicity of novel drugs on cardiac hERG (Langheinrich et al., 2003; Mittelstadt et al., 2008; Shi et al., 2009). The gene discussed is KCNH2; the disease is familial long QT syndrome.