It must be mentioned, while many companies are exploring IKuR inhibitors (see below) for treatment of AF, loss-of-function Kv1.5 mutations have been associated with atrial fibrillation.133,134 Loss of Kv1.5 protein has been detected in chronic AF patients; therefore, inhibiting this remaining current may not produce significant effects on ERP in this particular disease state.135. The gene discussed is KCNA5; the disease is atrial fibrillation.