A decrease in Kv7.1 conduction is a plausible cause for QT-interval prolongation arrhythmias, and since this type of arrhythmia is common in SSc, we investigated the effects of CO on recombinant Kv7.1 channels by means of whole-cell patch-clamp electrophysiology. The gene discussed is KCNQ1; the disease is cardiac arrhythmia.