This gene encodes a protein for a voltage-gated potassium channel required for the repolarization phase of the cardiac action potential.

KvLQT1 are also expressed in the pancreas, and KvLQT1 Long QT syndrome patients has been shown to have hyperinsulinemic hypoglycaemia following an oral glucose load.

Though physiologically irrelevant, homotetrameric Kv7.1 channels also display a unique form of C-type inactivation that reaches equilibrium quickly, allowing KvLQT1 currents to plateau.

[6] KCNQ1 will form a heteromer with KCNE1 in order to slow its activation and enhance the current density at the plasma membrane of the neuron.

[13] General mutations in KvLQT1 have been known to cause a decrease in this slow delayed potassium rectifier current, longer cardiac action potentials, and a tendency to have tachyarrhythmias.

KCNE1 slows the inactivation of KvLQT1 when the two proteins form a heteromeric complex, and the current amplitude is greatly increased compared to WT-KvLQT1 homotetrameric channels.

KCNE1 associates with the pore region of KvLQT1, and its transmembrane domain contributes to the selectivity filter of this heteromeric channel complex.