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Updated: Apr 17, 2026
Estimating Bilateral Atrial Function by Cardiovascular Magnetic Resonance Feature Tracking in Patients with Paroxysmal Atrial Fibrillation
Published on: July 20, 2022
Molecular genetic analysis of six Dutch families with atrial fibrillation
Insights
Genetic analysis of KCNQ1, KCNE1, and Cx40 genes in Dutch families with atrial fibrillation (AF) revealed no mutations. This suggests genetic heterogeneity in AF, warranting further research into other candidate genes and families.
Area of Science:
- Cardiovascular Genetics
- Molecular Cardiology
- Arrhythmology
Background:
- Atrial fibrillation (AF) is the most common cardiac arrhythmia, increasing with age and linked to stroke and mortality.
- Familial AF suggests a genetic component, but underlying mechanisms remain largely unknown.
- Previous studies identified mutations in KCNQ1 and KCNE2 genes, and altered connexin40 expression in AF.
Purpose of the Study:
- To investigate the role of KCNQ1, KCNE1 coding regions, and Cx40 promoter regions in six Dutch families with familial AF.
- To identify potential genetic variants contributing to the development of atrial fibrillation.
- To explore genetic heterogeneity in the etiology of familial AF.
Main Methods:
- Sequence analysis of the KCNQ1 gene.
- Sequence analysis of the KCNE1 coding region.
- Sequence analysis of the Cx40 promoter region in six Dutch AF families.
Main Results:
- No disease-causing mutations were identified in the analyzed KCNQ1, KCNE1, or Cx40 genes within the studied Dutch AF families.
- The absence of mutations in these candidate genes supports the hypothesis of genetic heterogeneity in familial AF.
- This finding underscores the complexity of AF genetics and the need for broader genetic investigations.
Conclusions:
- The study did not find mutations in KCNQ1, KCNE1, or Cx40, indicating these genes are not primary causes of AF in these Dutch families.
- Genetic heterogeneity is likely a significant factor in familial atrial fibrillation.
- Further research, including sequencing additional candidate genes and performing linkage analysis in larger families, is essential to unravel the genetic basis of AF.
Background:
Atrial fibrillation (AF), the most common cardiac arrhythmia, is characterised by rapid and irregular contraction of the atrium. The risk of AF increases with age and AF increases the risk of various heart disorders, stroke and mortality. AF can occur in a sporadic or familial form. The underlying mechanism leading to AF is not well known but genetic analysis can increase our insight into the molecular pathways in AF. Detailed information on the molecular mechanisms of a disorder increase options for diagnosis and treatment. Recently, a gain-of-function mutation in exon of the KCNQ1 gene located on chromosome 11 was identified in a large Chinese AF family. KCNQ1 associates with KCNE1 or KCNE2 (both located on chromosome 21) to form cardiac potassium channels. Subsequent analysis of Chinese families showed a KCNE2 mutation in two families. Other genetic studies show linkage to chromosome 6 and 10, indicating genetic heterogeneity. A number of studies have shown that altered expression of the atrial connexin40 protein is a risk factor for AF. Connexin genes encode gap-junction proteins that are important in cardiac conduction and for normal wave propagation.
Objectives/Methods:
In this study we analysed the role of KCNQ1, KCNE1 coding region and Cx40 promoter region in six Dutch AF families by sequence analysis.
Conclusion:
No mutations were found in these genes. The absence of mutations indicates genetic heterogeneity in familial AF; however, further research is needed. Candidate genes are being sequenced, linkage analysis in a large family will be performed and additional AF families will be collected.
