Gene-environment interaction between SCN5A-1103Y and hypokalemia influences QT interval prolongation in African Americans: The Jackson Heart Study

SCN5A-1103Y potentiates the effect of hypokalemia on prolonging myocardial repolarization in the general African-American population. These findings have clinical implications for modification of QT prolonging factors, such as hypokalemia, in the 15% of African Americans who are carriers of SCN5A-1103Y.