8 results found
Horvat C, Johnson R, Lam L, et al., 2019, A gene-centric strategy for identifying disease-causing rare variants in dilated cardiomyopathy, Genetics in Medicine, Vol: 21, Pages: 133-143, ISSN: 1098-3600
PurposeWe evaluated strategies for identifying disease-causing variants in genetic testing for dilated cardiomyopathy (DCM).MethodsCardiomyopathy gene panel testing was performed in 532 DCM patients and 527 healthy control subjects. Rare variants in 41 genes were stratified using variant-level and gene-level characteristics.ResultsA majority of DCM cases and controls carried rare protein-altering cardiomyopathy gene variants. Variant-level characteristics alone had limited discriminative value. Differentiation between groups was substantially improved by addition of gene-level information that incorporated ranking of genes based on literature evidence for disease association. The odds of DCM were increased to nearly 9-fold for truncating variants or high-impact missense variants in the subset of 14 genes that had the strongest biological links to DCM (P <0.0001). For some of these genes, DCM-associated variants appeared to be clustered in key protein functional domains. Multiple rare variants were present in many family probands, however, there was generally only one “driver” pathogenic variant that cosegregated with disease.ConclusionRare variants in cardiomyopathy genes can be effectively stratified by combining variant-level and gene-level information. Prioritization of genes based on their a priori likelihood of disease causation is a key factor in identifying clinically actionable variants in cardiac genetic testing.
Tayal U, Newsome S, Buchan R, et al., 2017, Phenotype and Clinical Outcomes of Titin Cardiomyopathy, Journal of the American College of Cardiology, Vol: 70, Pages: 2264-2274, ISSN: 0735-1097
Background Improved understanding of dilated cardiomyopathy (DCM) due to titin truncation (TTNtv) may help guide patient stratification.Objectives The purpose of this study was to establish relationships among TTNtv genotype, cardiac phenotype, and outcomes in DCM.Methods In this prospective, observational cohort study, DCM patients underwent clinical evaluation, late gadolinium enhancement cardiovascular magnetic resonance, TTN sequencing, and adjudicated follow-up blinded to genotype for the primary composite endpoint of cardiovascular death, and major arrhythmic and major heart failure events.Results Of 716 subjects recruited (mean age 53.5 ± 14.3 years; 469 men [65.5%]; 577 [80.6%] New York Heart Association function class I/II), 83 (11.6%) had TTNtv. Patients with TTNtv were younger at enrollment (49.0 years vs. 54.1 years; p = 0.002) and had lower indexed left ventricular mass (5.1 g/m2 reduction; padjusted = 0.03) compared with patients without TTNtv. There was no difference in biventricular ejection fraction between TTNtv+/− groups. Overall, 78 of 604 patients (12.9%) met the primary endpoint (median follow-up 3.9 years; interquartile range: 2.0 to 5.8 years), including 9 of 71 patients with TTNtv (12.7%) and 69 of 533 (12.9%) without. There was no difference in the composite primary outcome of cardiovascular death, heart failure, or arrhythmic events, for patients with or without TTNtv (hazard ratio adjusted for primary endpoint: 0.92 [95% confidence interval: 0.45 to 1.87]; p = 0.82).Conclusions In this large, prospective, genotype-phenotype study of ambulatory DCM patients, we show that prognostic factors for all-cause DCM also predict outcome in TTNtv DCM, and that TTNtv DCM does not appear to be associated with worse medium-term prognosis.
Fatkin D, Lam L, Herman DS, et al., 2016, Titin truncating mutations: a rare cause of dilated cardiomyopathy in the young, Progress in Pediatric Cardiology, Vol: 40, Pages: 41-45, ISSN: 1058-9813
Truncating mutations in the TTN gene are the most common genetic cause of dilated cardiomyopathy in adults but their role in young patients is unknown. We studied 82 young dilated cardiomyopathy subjects and found that the prevalence of truncating TTN mutations in adolescents was similar to adults, but surprisingly few truncating TTN mutations were identified in affected children, including one confirmed de novo variant. In several cases, truncating TTN mutations in children with dilated cardiomyopathy had evidence of additional clinical or genetic risk factors. These findings have implications for genetic testing and suggest that single truncating TTN mutations are insufficient alone to cause pediatric-onset dilated cardiomyopathy.
Roberts AM, Ware JS, Herman DS, et al., 2015, Integrated allelic, transcriptional, and phenomic dissection of the cardiac effects of titin truncations in health and disease., Sci Transl Med, Vol: 7
The recent discovery of heterozygous human mutations that truncate full-length titin (TTN, an abundant structural, sensory, and signaling filament in muscle) as a common cause of end-stage dilated cardiomyopathy (DCM) promises new prospects for improving heart failure management. However, realization of this opportunity has been hindered by the burden of TTN-truncating variants (TTNtv) in the general population and uncertainty about their consequences in health or disease. To elucidate the effects of TTNtv, we coupled TTN gene sequencing with cardiac phenotyping in 5267 individuals across the spectrum of cardiac physiology and integrated these data with RNA and protein analyses of human heart tissues. We report diversity of TTN isoform expression in the heart, define the relative inclusion of TTN exons in different isoforms (using the TTN transcript annotations available at http://cardiodb.org/titin), and demonstrate that these data, coupled with the position of the TTNtv, provide a robust strategy to discriminate pathogenic from benign TTNtv. We show that TTNtv is the most common genetic cause of DCM in ambulant patients in the community, identify clinically important manifestations of TTNtv-positive DCM, and define the penetrance and outcomes of TTNtv in the general population. By integrating genetic, transcriptome, and protein analyses, we provide evidence for a length-dependent mechanism of disease. These data inform diagnostic criteria and management strategies for TTNtv-positive DCM patients and for TTNtv that are identified as incidental findings.
Ware JS, John S, Roberts AM, et al., 2013, Next Generation Diagnostics in Inherited Arrhythmia Syndromes, JOURNAL OF CARDIOVASCULAR TRANSLATIONAL RESEARCH, Vol: 6, Pages: 94-103, ISSN: 1937-5387
Ware JS, Roberts AM, Cook SA, 2012, Republished review: Next generation sequencing for clinical diagnostics and personalised medicine: implications for the next generation cardiologist, POSTGRADUATE MEDICAL JOURNAL, Vol: 88, Pages: 234-239, ISSN: 0032-5473
Ware JS, Roberts AM, Cook SA, 2012, Next generation sequencing for clinical diagnostics and personalised medicine: implications for the next generation cardiologist, HEART, Vol: 98, Pages: 276-281, ISSN: 1355-6037
Villard E, Perret C, Gary F, et al., 2011, A genome-wide association study identifies two loci associated with heart failure due to dilated cardiomyopathy, EUROPEAN HEART JOURNAL, Vol: 32, Pages: 1065-1076, ISSN: 0195-668X
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.