KCNQ1 gene encodes a protein named potassium voltage-gated channel subfamily KQT member 1 that plays a critical role in regulating repolarisation phase of the cardiac action potential as well as in controlling the water and salt homeostasis in several epithelial tissues. Mutations in KCNQ1 gene are associated with hereditary long QT syndrome 1 (also known as Romano-Ward syndrome), Jervell and Lange-Nielsen syndrome, and familial atrial fibrillation. These mutations affect the voltage-gated K+ channel resulting in reduction of potassium ion transport, thereby, altering the transmission of electrical signals in the heart and consequently increasing the risk of syncope or sudden death to occur.