Moleculogenetic Characteristics of the Patient with Long QT Syndrome in Korean

BACKGROUND AND OBJECTIVES: Congenital long QT syndrome (LQTS) is a genetic disease that brings prolongation of the QT interval on an electrocardiogram and leads to syncope and sudden death by a fatal ventricular arrhythmia. In Korea, there have been studies about the clinical characteristics and treatment of LQTS, but there are no studies for the molecular and biological evaluation of its genetic mutation.

SUBJECTS AND METHODS: Six nationwide university hospitals and laboratories segregated DNA from the blood of 10 patients diagnosed with LQTS to analyze the genetic mutation.

RESULTS: Nine out of ten individuals were female. Eight showed genetic mutations. Three had an abnormality in the KvLQT1, 6 in the HERG and 2 had abnormalities in both KvLQT1 and HERG. None had abnormalities in KCNE1 and 2 showed no abnormalities in KvLQT1, HERG or KCNE1.

CONCLUSION: Congenital LQTS shows various genetic mutations, and this indicates the necessity for further organized study in more individuals for confirmation of the relationship between the results of clinical diagnosis and genetic analysis.