The patients with LQTS carried the following variants in KCNQ1 (NM_000218.3): p.(Arg366Gln) (2 patients), p.(Arg231Cys) (6 patients), p.(Arg249Gly), and p.(Asp242Asn) (2 patients); the following variants in KCNH2 (NM_000238.3): p.(Asp509Asn), p.(Arg1512Trp), p.(Arg1014*), p.(Arg863*) (3 patients), p.(Ala561Val) (2 patients), p.(Arg531Trp) (3 patients), p.(Glu698*), and p.(Arg176Trp); and the following variants in SCN5A (NM_198056.2): p.(Arg1512Trp), p.(Gln1507_Pro1509del) (2 patients), and p.(Asn1774His). Here, SCN5A is linked to familial long QT syndrome.