Aims: The QT interval in the general population is a complex trait with 30-50% heritability. QT prolongation is associated with an increased risk of sudden death. A recent family-based study found an association between QT interval and the common non-synonymous Glycin 38 Serine variant (G38S, rs1805127) of the KCNE1 gene coding for the minK-potassium channel subunit. We intended to replicate this finding in a large population sample of central European Caucasian ancestry as part of our ongoing search for genetic variants predisposing to arrhythmias.
Methods and results: We studied 3966 unrelated individuals from the KORA S4 population-based study without atrial fibrillation, pacemaker implant, or pregnancy. Individuals were genotyped by MALDI-TOF mass spectrometry. We did not detect any significant association between the genotypes of the G38S variant and the QT interval in the entire population or in any gender.
Conclusion: Unlike the common Lysine 897 Threonine variant of KCNH2 (K897T, rs1805123) the G38S variant of KCNE1 does not appear to have a strong modifying effect on QT interval. However, we cannot rule out an effect of G38S on QT in other ethnic groups, under exercise or medications or on the risk for arrhythmias and sudden death.