Gene symbol: KCNQ1

A 12-year-old white female was referred to our attention for a suspected Long QT syndrome. The clinical history was negative for cardiac events; the girl simpty referred episodes of palpitations. The family history was negative for syncope or sudden cardiac death; however also the mother's ECG showed a clear QTc prolongation (QTc 490 ms in D2). Echocardiography showed normal features. LQTS genes were screened through DHPLC and sequence analysis. A novel transversion predicting the missense Gln367His was identified in the Cterminal region of KCNQ1. The Gln 367 is highly conserved among different species. The same mutation was identified in the proband and in her mother and was not identifled in 150 controls. à