KCNQ1 and Prolonged QT interval: In addition to cardiac rhythm defects, patients with Jervell and Lange-Nielsen syndrome have deafness from birth.105 Mutation of the accessory protein MinK has been shown to be associated with long QT syndrome 5106 and atrial fibrillation,107 while gain-of-function mutations of KV7.1 are associated with short QT syndrome 2 and familial atrial fibrillation type 3.108,109