The rationale behind using these genes as candidates in LQTS in reported studies relied on precedent in which some multiple-organ syndromes may present with a cardiac-specific phenotype in isolation (eg, Fabry disease).27 Nevertheless, the Working Group found only limited evidence for KCNJ2 as a disease-causing gene in isolated LQTS. The gene discussed is KCNJ2; the disease is familial long QT syndrome.