1. From the Institut für Humangenetik (N.M., C.G., R.R., A.H., K.S., G.R.), Universität Heidelberg, and the Abteilung für Kardiologie (H.R., H.U.), Kinderklinik Heidelberg, Heidelberg, Germany; the Division of Cardiology (E.G., D.D.), Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, Pa; and the Institute of Human Genetics (J.G.), International Center for Life, Newcastle upon Tyne, Great Britain.