This is the first report that the S1103Y variant is associated with a higher incidence of ventricular arrhythmias in blacks with heart failure and reduced ejection fraction.
We found that the rs1805126 minor allele associates with decreased cardiac SCN5A expression and that heart failure subjects homozygous for the minor allele have decreased ejection fraction and increased mortality, but not increased ventricular tachyarrhythmias.