Dataset Information

Non-familial cardiomyopathies in Lebanon: exome sequencing results for five idiopathic cases.

ABSTRACT: BACKGROUND:Cardiomyopathies affect more than 0.5% of the general population. They are associated with high risk of sudden cardiac death, which can result from either heart failure or electrical abnormalities. Although different mechanisms underlie the various types of cardiomyopathies, a principal pathology is common to all and is usually at the level of the cardiac muscle. With a relatively high incidence rate in most countries, and a subsequent major health burden on both the families and governments, cardiomyopathies are gaining more attention by researchers and pharmaceutical companies as well as health government bodies. In Lebanon, there is no official data about the spectrum of the diseases in terms of their respective prevalence, clinical, or genetic profiles. METHODS:We used exome sequencing to unravel the genetic basis of idiopathic cases of cardiomyopathies in Lebanon, a relatively small country with high rates of consanguineous marriages. RESULTS:Five cases were diagnosed with different forms of cardiomyopathies, and exome sequencing revealed the presence of already documented or novel mutations in known genes in three cases: LMNA for an Emery Dreifuss Muscular Dystrophy case, PKP2 for an arrhythmogenic right ventricle dysplasia case, and MYPN for a dilated cardiomyopathy case. Interestingly two brothers with hypertrophic cardiomyopathy have a novel missense variation in NPR1, the gene encoding the natriuretic peptides receptor type I, not reported previously to be causing cardiomyopathies. CONCLUSION:Our results unravel novel mutations in known genes implicated in cardiomyopathies in Lebanon. Changes in clinical management however, require genetic profiling of a larger cohort of patients.

SUBMITTER: Refaat MM

PROVIDER: S-EPMC6375196 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Non-familial cardiomyopathies in Lebanon: exome sequencing results for five idiopathic cases.

Refaat Marwan M MM Hassanieh Sylvana S Ballout Jad A JA Zakka Patrick P Hotait Mostafa M Khalil Athar A Bitar Fadi F Arabi Mariam M Arnaout Samir S Skouri Hadi H Abchee Antoine A Abi-Saleh Bernard B Khoury Maurice M Massouras Andreas A Nemer Georges G

BMC medical genomics 20190214 1

<h4>Background</h4>Cardiomyopathies affect more than 0.5% of the general population. They are associated with high risk of sudden cardiac death, which can result from either heart failure or electrical abnormalities. Although different mechanisms underlie the various types of cardiomyopathies, a principal pathology is common to all and is usually at the level of the cardiac muscle. With a relatively high incidence rate in most countries, and a subsequent major health burden on both the families ...[more]

PMID: 30764827

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Project description:ImportanceComplex disorders, such as bipolar disorder (BD), likely result from the influence of both common and rare susceptibility alleles. While common variation has been widely studied, rare variant discovery has only recently become feasible with next-generation sequencing.ObjectiveTo utilize a combined family-based and case-control approach to exome sequencing in BD using multiplex families as an initial discovery strategy, followed by association testing in a large case-control meta-analysis.Design, setting, and participantsWe performed exome sequencing of 36 affected members with BD from 8 multiplex families and tested rare, segregating variants in 3 independent case-control samples consisting of 3541 BD cases and 4774 controls.Main outcomes and measuresWe used penalized logistic regression and 1-sided gene-burden analyses to test for association of rare, segregating damaging variants with BD. Permutation-based analyses were performed to test for overall enrichment with previously identified gene sets.ResultsWe found 84 rare (frequency <1%), segregating variants that were bioinformatically predicted to be damaging. These variants were found in 82 genes that were enriched for gene sets previously identified in de novo studies of autism (19 observed vs. 10.9 expected, P = .0066) and schizophrenia (11 observed vs. 5.1 expected, P = .0062) and for targets of the fragile X mental retardation protein (FMRP) pathway (10 observed vs. 4.4 expected, P = .0076). The case-control meta-analyses yielded 19 genes that were nominally associated with BD based either on individual variants or a gene-burden approach. Although no gene was individually significant after correction for multiple testing, this group of genes continued to show evidence for significant enrichment of de novo autism genes (6 observed vs 2.6 expected, P = .028).Conclusions and relevanceOur results are consistent with the presence of prominent locus and allelic heterogeneity in BD and suggest that very large samples will be required to definitively identify individual rare variants or genes conferring risk for this disorder. However, we also identify significant associations with gene sets composed of previously discovered de novo variants in autism and schizophrenia, as well as targets of the FRMP pathway, providing preliminary support for the overlap of potential autism and schizophrenia risk genes with rare, segregating variants in families with BD.

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Dataset Information

Non-familial cardiomyopathies in Lebanon: exome sequencing results for five idiopathic cases.

Publications

Non-familial cardiomyopathies in Lebanon: exome sequencing results for five idiopathic cases.

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