title: Three generations of hereditary long-QT syndrome with complete penetrance caused by the p.G316E KCNQ1 mutation.
abstract: 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.
authors.affiliation: Cardiology Division, Pediatric Department, University Hospital Marqués de Valdecilla, Cazoña s/n, 39008 Santander, Spain.
authors.forename: M Teresa
authors.initials: MT
authors.lastname: Viadero
authors.forename: Esther
authors.initials: E
authors.lastname: Rubín
authors.forename: Teresa
authors.initials: T
authors.lastname: Amigo
authors.forename: Domingo
authors.initials: D
authors.lastname: González-Lamuño
mesh_terms: D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D051657:KCNQ1 Potassium Channel; D008297:Male; D020125:Mutation, Missense; D010375:Pedigree; D029597:Romano-Ward Syndrome / Q000235:genetics*
chemical_list: D051657:KCNQ1 Potassium Channel; C496909:KCNQ1 protein, human