KChIP2 (Kv Channel-Interacting Protein 2) is preferentially expressed in the adult heart and has a role in sustaining the normal rhythmic beating, but its role in cardiac pathology remains unclear. In December 14 Cell, Hai-Chien Kuo and colleagues from University of California, San Diego, La Jolla, USA, show that a defect in KChIP2 is sufficient to confer a marked genetic susceptibility to ventricular tachycardia that would ordinarily lead to sudden death in humans.

Kuo et al. used KChIP2-/- mice and observed that they had no physical abnormalities of the heart, but a single extra heartbeat could induce a sustained malignant heart rhythm that would ordinarily lead to sudden death in humans. This was caused by a complete absence of the transient outward potassium current, I_to, and a marked increase in action potential duration (Cell 2001, 107:801-813).

"We now know that this...