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Several common variants modulate heart rate, PR interval and QRS duration
Hilma Holm1, Daniel F Gudbjartsson, David O Arnar
1deCODE genetics, Reykjavik, Iceland. hilma.holm@decode.is
Nature Genetics
|January 12, 2010
Summary
This study identified genetic variants influencing heart rate, PR interval, and QRS duration. These findings link specific genes to cardiac arrhythmias like atrial fibrillation and heart block.
Area of Science:
- Cardiovascular Genetics
- Genomics
- Electrophysiology
Background:
- Electrocardiographic (ECG) measures reflect cardiac conduction system function.
- Identifying genetic factors influencing ECG traits is crucial for understanding heart rate and rhythm regulation.
Purpose of the Study:
- To discover sequence variants associated with heart rate, PR interval, and QRS duration.
- To investigate the role of identified genetic loci in cardiac arrhythmias.
Main Methods:
- Genome-wide association study (GWAS) in ~20,000 individuals of European descent.
- Replication of top signals in independent cohorts.
- Case-control association testing for arrhythmias in Icelandic and Norwegian samples.
Main Results:
- Identified genome-wide significant associations for heart rate (MYH6), PR interval (TBX5, SCN10A, CAV1, ARHGAP24), and QRS duration (TBX5, SCN10A, 6p21, 10q21).
- TBX5 and CAV1 associated with atrial fibrillation.
- TBX5 associated with advanced atrioventricular block.
- SCN10A associated with pacemaker implantation.
- Replicated known QT interval associations.
Conclusions:
- This GWAS successfully identified novel genetic loci influencing key ECG parameters.
- Specific genes like TBX5, CAV1, and SCN10A show significant associations with cardiac arrhythmias, highlighting their roles in cardiac electrical function and disease.
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