Pediatric Cardiology

, Volume 32, Issue 1, pp 102–104 | Cite as

Three Generations of Hereditary Long-QT Syndrome with Complete Penetrance Caused by the p.G316E KCNQ1 Mutation

  • M. Teresa Viadero
  • Esther Rubín
  • Teresa Amigo
  • Domingo González-Lamuño
Case Report


This report describes a three-generation family with a severe phenotype of long-QT syndrome-1 (LQTS-1) caused by a single nucleotide mutation in the KQT-like, voltage-gated potassium channel-1 gene (KCNQ1; MIM 607542). Two members of the family died suddenly in their childhood, and all eight surviving members with prolonged QT have a heterozygous missense mutation resulting in a glycine-to-glutamate amino acid substitution at position 316 of the potassium channel. In this family, the newly reported mutation, guanine-to-adenosine at position 947 in the KCNQ1 gene, exhibits a dominant trait of LQTS with complete penetrance, in contrast to the relatively reduced clinical penetrance found in most LQTS cases.


Genetic mutation KCNQ1 channel Long-QT syndrome 


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • M. Teresa Viadero
    • 1
  • Esther Rubín
    • 2
  • Teresa Amigo
    • 3
  • Domingo González-Lamuño
    • 3
    • 4
  1. 1.Cardiology Division, Pediatric DepartmentUniversity Hospital Marqués de ValdecillaSantanderSpain
  2. 2.Pediatric DepartmentUniversity Hospital Marques de ValdecillaSantanderSpain
  3. 3.Genetic and Pediatric Division, School of MedicineUniversity of CantabriaSantanderSpain
  4. 4.Pediatric DepartmentResearch Institute and University Hospital “Marques de Valdecilla” (IFIMAV)SantanderSpain

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