Dataset Information

A Novel Loss-of-Function Variant in the Chloride Ion Channel Gene Clcn2 Associates with Atrial Fibrillation.

ABSTRACT: Atrial Fibrillation (AF) is the most common cardiac arrhythmia. Its pathogenesis is complex and poorly understood. Whole exome sequencing of Danish families with AF revealed a novel four nucleotide deletion c.1041_1044del in CLCN2 shared by affected individuals. We aimed to investigate the role of genetic variation of CLCN2 encoding the inwardly rectifying chloride channel ClC-2 as a risk factor for the development of familiar AF. The effect of the CLCN2 variant was evaluated by electrophysiological recordings on transiently transfected cells. We used quantitative PCR to assess CLCN2 mRNA expression levels in human atrial and ventricular tissue samples. The nucleotide deletion CLCN2 c.1041_1044del results in a frame-shift and premature stop codon. The truncated ClC-2 p.V347fs channel does not conduct current. Co-expression with wild-type ClC-2, imitating the heterozygote state of the patients, resulted in a 50% reduction in macroscopic current, suggesting an inability of truncated ClC-2 protein to form channel complexes with wild type channel subunits. Quantitative PCR experiments using human heart tissue from healthy donors demonstrated that CLCN2 is expressed across all four heart chambers. Our genetic and functional data points to a possible link between loss of ClC-2 function and an increased risk of developing AF.

SUBMITTER: Hansen TH

PROVIDER: S-EPMC6989500 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A Novel Loss-of-Function Variant in the Chloride Ion Channel Gene Clcn2 Associates with Atrial Fibrillation.

Hansen Thea Hyttel TH Yan Yannan Y Ahlberg Gustav G Vad Oliver Bundgaard OB Refsgaard Lena L Dos Santos Joana Larupa JL Mutsaers Nancy N Svendsen Jesper Hastrup JH Olesen Morten Salling MS Bentzen Bo Hjorth BH Schmitt Nicole N

Scientific reports 20200129 1

Atrial Fibrillation (AF) is the most common cardiac arrhythmia. Its pathogenesis is complex and poorly understood. Whole exome sequencing of Danish families with AF revealed a novel four nucleotide deletion c.1041_1044del in CLCN2 shared by affected individuals. We aimed to investigate the role of genetic variation of CLCN2 encoding the inwardly rectifying chloride channel ClC-2 as a risk factor for the development of familiar AF. The effect of the CLCN2 variant was evaluated by electrophysiolog ...[more]

PMID: 31996765

Similar Datasets

Project description:Importance:Atrial fibrillation (AF) is the most common arrhythmia affecting 1% of the population. Young individuals with AF have a strong genetic association with the disease, but the mechanisms remain incompletely understood. Objective:To perform large-scale whole-genome sequencing to identify genetic variants related to AF. Design, Setting, and Participants:The National Heart, Lung, and Blood Institute's Trans-Omics for Precision Medicine Program includes longitudinal and cohort studies that underwent high-depth whole-genome sequencing between 2014 and 2017 in 18?526 individuals from the United States, Mexico, Puerto Rico, Costa Rica, Barbados, and Samoa. This case-control study included 2781 patients with early-onset AF from 9 studies and identified 4959 controls of European ancestry from the remaining participants. Results were replicated in the UK Biobank (346?546 participants) and the MyCode Study (42?782 participants). Exposures:Loss-of-function (LOF) variants in genes at AF loci and common genetic variation across the whole genome. Main Outcomes and Measures:Early-onset AF (defined as AF onset in persons <66 years of age). Due to multiple testing, the significance threshold for the rare variant analysis was P?=?4.55?×?10-3. Results:Among 2781 participants with early-onset AF (the case group), 72.1% were men, and the mean (SD) age of AF onset was 48.7 (10.2) years. Participants underwent whole-genome sequencing at a mean depth of 37.8 fold and mean genome coverage of 99.1%. At least 1 LOF variant in TTN, the gene encoding the sarcomeric protein titin, was present in 2.1% of case participants compared with 1.1% in control participants (odds ratio [OR], 1.76 [95% CI, 1.04-2.97]). The proportion of individuals with early-onset AF who carried a LOF variant in TTN increased with an earlier age of AF onset (P value for trend, 4.92?×?10-4), and 6.5% of individuals with AF onset prior to age 30 carried a TTN LOF variant (OR, 5.94 [95% CI, 2.64-13.35]; P?=?1.65?×?10-5). The association between TTN LOF variants and AF was replicated in an independent study of 1582 patients with early-onset AF (cases) and 41?200 control participants (OR, 2.16 [95% CI, 1.19-3.92]; P?=?.01). Conclusions and Relevance:In a case-control study, there was a statistically significant association between an LOF variant in the TTN gene and early-onset AF, with the variant present in a small percentage of participants with early-onset AF (the case group). Further research is necessary to understand whether this is a causal relationship.

Dataset Information

A Novel Loss-of-Function Variant in the Chloride Ion Channel Gene Clcn2 Associates with Atrial Fibrillation.

Publications

A Novel Loss-of-Function Variant in the Chloride Ion Channel Gene Clcn2 Associates with Atrial Fibrillation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets