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Updated: Feb 4, 2026

Genotyping Single Nucleotide Polymorphisms in the Mitochondrial Genome by Pyrosequencing
Published on: February 10, 2023
The narrow-sense and common single nucleotide polymorphism heritability of early repolarization
Rachel Bastiaenen1, Ilja M Nolte2, Patricia B Munroe3
1Molecular and Clinical Sciences Research Institute, St George's University of London, UK.
Background:
Early repolarization (ER) is a risk marker for sudden cardiac death. Higher risk is associated with horizontal/descending ST-segment ER in the inferior or inferolateral ECG leads. Studies in family cohorts have demonstrated substantial heritability for the ER pattern, but genome-wide association studies (GWAS) have failed to identify statistically significant and replicable genetic signals.
Methods And Results:
We assessed the narrow-sense and common single nucleotide polymorphism (SNP) heritability of ER and ER subtypes using ECG data from 5829 individuals (TwinsUK, BRIGHT and GRAPHIC cohorts). ER prevalence was 8.3%. In 455 monozygous vs 808 dizygous twin pairs, concordances and twin correlations for ER subtypes (except horizontal/descending ST-segment ER) were higher and familial resemblance (except notched ER) was significant. Narrow-sense heritability estimates derived from 1263 female twin pairs using the structural equation program Mx ranged from 0.00-0.47 and common SNP heritability estimates derived from 4009 unrelated individuals of both sexes using Genome-wide Restricted Maximum Likelihood (GREML) ranged from 0.00-0.36, but none were statistically significant.
Conclusion:
From our data, ER shows limited genetic predisposition. There appears to be significant environmental influence and these modest narrow-sense and common SNP heritability estimates may explain why previous GWAS have been unsuccessful.
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