Published in:
01-04-2015
Enhancing the Predictive Power of Mutations in the C-Terminus of the KCNQ1-Encoded Kv7.1 Voltage-Gated Potassium Channel
Authors:
Jamie D. Kapplinger, Andrew S. Tseng, Benjamin A. Salisbury, David J. Tester, Thomas E. Callis, Marielle Alders, Arthur A. M. Wilde, Michael J. Ackerman
Published in:
Journal of Cardiovascular Translational Research
|
Issue 3/2015
Login to get access
Abstract
Despite the overrepresentation of Kv7.1 mutations among patients with a robust diagnosis of long QT syndrome (LQTS), a background rate of innocuous Kv7.1 missense variants observed in healthy controls creates ambiguity in the interpretation of LQTS genetic test results. A recent study showed that the probability of pathogenicity for rare missense mutations depends in part on the topological location of the variant in Kv7.1’s various structure-function domains. Since the Kv7.1’s C-terminus accounts for nearly 50 % of the overall protein and nearly 50 % of the overall background rate of rare variants falls within the C-terminus, further enhancement in mutation calling may provide guidance in distinguishing pathogenic long QT syndrome type 1 (LQT1)-causing mutations from rare non-disease-causing variants in the Kv7.1’s C-terminus. Therefore, we have used conservation analysis and a large case-control study to generate topology-based estimative predictive values to aid in interpretation, identifying three regions of high conservation within the Kv7.1’s C-terminus which have a high probability of LQT1 pathogenicity.