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Updated: Jul 12, 2025

Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation
Published on: January 16, 2019
Clinical Heterogeneity in Patients with Long QT Syndrome and Segregation of Single Nucleotide Variants and Clinical
Elcin Bora1, Ayca Yıldız Bulut1, Tufan Cankaya1
1Department of Medical Genetics, Dokuz Eylul University Faculty of Medicine, Izmir, Turkey.
Introduction:
Long QT syndrome (LQTS) is a disorder of ventricular myocardial repolarization characterized by a prolonged QT interval on the electrocardiogram. It increases the risk of ventricular arrhythmias, which can cause syncope or sudden cardiac death. In this study, we study the genotype-phenotype relationships of patients referred to us with suspected arrhythmia syndrome.
Methods:
Seventeen cases and their twenty relatives were evaluated. Next-generation sequencing analysis was performed for 17 LQTS-related genes.
Results:
We detected seventeen single nucleotide variants (SNVs) with potential pathogenic significance in 26 of the 36 subjects analyzed. KCNH2 c.172G>A, KCNQ1 c.1768G>A, ANK2 c.4666A>T, c.1484_1485delCT, KCNH2 c.1888G>A were reported as pathogenic or likely pathogenic in HGMD variant classification database.
Conclusion:
Current study pointed out that early diagnosis can be life-saving for patients and their families by taking family history and detailed examination. Also, we highlight the clinical heterogeneity of arrhythmia syndrome through a patient with a dual phenotype.
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