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Updated: Jun 14, 2026
07:15
Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation
Published on: January 16, 2019
[Genetic in long QT syndromes]
Pedro Iturralde-Torres1, Argelia Medeiros-Domingo
1Servicio de Electrofisiología, Instituto Nacional de Cardiología Ignacio Chávez. pedro@yahoo.com
Archivos De Cardiologia De Mexico
|April 6, 2010
Summary
Long QT syndrome (LQTS) is a genetic heart condition causing dangerous arrhythmias. Genetic testing is crucial for diagnosing LQTS, especially when ECG findings are unclear.
Area of Science:
- Cardiology
- Genetics
- Molecular Biology
Context:
- Long QT syndrome (LQTS) is a genetic disorder affecting young individuals.
- It is characterized by QT interval prolongation on ECG and risk of fatal arrhythmias.
- LQTS arises from ion channel gene mutations causing myocardial electrical instability.
Purpose:
- To summarize the pathophysiology, diagnosis, and genetic basis of Long QT syndrome.
- To highlight the role of ECG and genetic testing in LQTS diagnosis.
- To underscore the genetic heterogeneity and diagnostic challenges in LQTS.
Summary:
- LQTS results from ion channel gene mutations leading to heterogeneous myocardial repolarization and early afterdepolarizations.
- Diagnosis involves patient/family history and ECG analysis, but 25-30% remain genetically undiagnosed.
- Over 500 mutations in 10 genes are known, with genetic testing vital for ambiguous cases.
Impact:
- Improved understanding of LQTS pathophysiology and genetic underpinnings.
- Enhanced diagnostic strategies for LQTS, particularly in challenging cases.
- Facilitates personalized risk assessment and management for LQTS patients.
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