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Patient with syncope and LQTS carrying a mutation in the PAS domain of the hERG1 channel.

ABSTRACT: We report the case of a woman with syncope and persistently prolonged QTc interval. Screening of congenital long QT syndrome (LQTS) genes revealed that she was a heterozygous carrier of a novel KCNH2 mutation, c.G238C. Electrophysiological and biochemical characterizations unveiled the pathogenicity of this new mutation, displaying a 2-fold reduction in protein expression and current density due to a maturation/trafficking-deficient mechanism. The patient's phenotype can be fully explained by this observation. This study illustrates the importance of performing genetic analyses and mutation characterization when there is a suspicion of congenital LQTS. Identifying mutations in the PAS domain or other domains of the hERG1 channel and understanding their effect may provide more focused and mutation-specific risk assessment in this population.

SUBMITTER: Grilo LS

PROVIDER: S-EPMC6932128 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Patient with syncope and LQTS carrying a mutation in the PAS domain of the hERG1 channel.

Grilo Liliana Sintra LS Schläpfer Jürg J Fellmann Florence F Abriel Hugues H

Annals of noninvasive electrocardiology : the official journal of the International Society for Holter and Noninvasive Electrocardiology, Inc 20110401 2

We report the case of a woman with syncope and persistently prolonged QTc interval. Screening of congenital long QT syndrome (LQTS) genes revealed that she was a heterozygous carrier of a novel KCNH2 mutation, c.G238C. Electrophysiological and biochemical characterizations unveiled the pathogenicity of this new mutation, displaying a 2-fold reduction in protein expression and current density due to a maturation/trafficking-deficient mechanism. The patient's phenotype can be fully explained by th ...[more]

PMID: 21496174

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