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Updated: Aug 23, 2025

Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation
Published on: January 16, 2019
Same family, same mutation, different ECG
Kürşat Akbuğa1, Mustafa Karanfil2
1Cardiology Department, Faculty of Medicine, TOBB ETU, Ankara, Turkey.
Background:
Different types of long QT syndromes (LQTS) have distinct ECG manifestations according to the type and magnitude of ion channel dysfunction. While LQT1 carriers usually have broad-based T waves and LQT3 carriers have extended ST segments with relatively narrow peaked T waves; LQT2 carriers have low-amplitude T waves with high incidences of notches.
Methods:
We describe three members of a family with the same LQTS2 pathogenic variant, but different surface ECG findings.
Conclusion:
This case shows ECG differences may also occur between family members who have pathogenic variants associated with long QT syndrome.
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