Newton-Cheh Christopher, Shah Ripal
Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, NHLBI's Framingham Heart Study, Cardiology Division, Massachusetts General Hospital, Boston, MA 02114, USA.
Curr Opin Genet Dev. 2007 Jun;17(3):213-21. doi: 10.1016/j.gde.2007.04.010. Epub 2007 Apr 30.
Electrocardiographic QT interval prolongation or shortening is a risk factor for sudden cardiac death. The study of Mendelian syndromes in families with extreme long and short QT interval duration and ventricular arrhythmias has led to the identification of genes encoding ion channel proteins important in myocardial repolarization. Rare mutations in such ion channel genes do not individually contribute substantially to the population burden of ventricular arrhythmias and sudden cardiac death. Only now are studies systematically testing the relationship between common variants in these genes--or elsewhere in the genome--and QT interval variation and sudden cardiac death. Identification of genetic variation underlying myocardial repolarization could have important implications for the prevention of both sporadic and drug-induced arrhythmias.
心电图QT间期延长或缩短是心源性猝死的一个危险因素。对QT间期极长和极短且伴有室性心律失常的家族中的孟德尔综合征进行研究，已导致鉴定出在心肌复极过程中起重要作用的编码离子通道蛋白的基因。此类离子通道基因中的罕见突变单独对室性心律失常和心源性猝死的人群负担贡献不大。直到现在，才有研究系统地测试这些基因（或基因组其他位置）的常见变异与QT间期变异和心源性猝死之间的关系。鉴定心肌复极潜在的遗传变异可能对散发性和药物性心律失常的预防具有重要意义。
