Genetic testing - Romano-Ward syndrome ... (See Long QT types 1 to 13).

See:

Long QT types 1 to 13, syndrome ... (Long QT syndrome - LQTS-) - Genes KCNQ1, KCNH2, SCN5A, ANK2, KCNE1, KCNE2, KCNJ2, CPVT1, CAV3, KCNJ5, CACNA1C and SCN4B.