From the Division of Genomic Medicine, University of Sheffield, Sheffield, UK (S.A.C., M.D.T., K.K.H., M.E.D.); the Department of Cardiology, University of Leicester, Leicester, UK (N.J.S.); and the Department of Cardiology, Royal Hallamshire Hospital, Sheffield, UK (R.P.S., K.S.C.). (At 2001-09-25)