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Ormondroyd E, Grace C, Borsari W, Goel A, McDonough B, Rose J, Seidman C, Watkins H. Genetic therapies for cardiomyopathy: survey of attitudes of the patient community for the CureHeart project. Eur J Hum Genet 2024:10.1038/s41431-024-01660-5. [PMID: 38972962 DOI: 10.1038/s41431-024-01660-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 06/16/2024] [Accepted: 06/25/2024] [Indexed: 07/09/2024] Open
Abstract
Cardiomyopathies are a group of inherited heart muscle disorders. Expressivity is variable and while sometimes mild, complications can result in sudden cardiac death (SCD) at any age, heart failure and stroke. In around a third of patients a monogenic cause is identifiable, and development of genetic therapies that aim to correct the underlying genetic defect is underway. Here we describe results of a survey designed to understand preliminary views of the patient community about genetic therapies in the context of disease burden. The internet survey was publicized with a bespoke information video via patient support groups in the UK and USA; 634 people responded of whom 96% had a personal and/or family history of cardiomyopathy. Findings show that concern about cardiomyopathy-related issues with a future dimension, such as disease progression, is significantly greater than concern about current issues. A total of 93.6% thought that genetic therapies should be developed for cardiomyopathy. A majority would consider participation in a genetic therapy trial in six scenarios varying by age and clinical situation significantly more in the scenario of an adult with symptomatic disease and evident progression than an asymptomatic adult with SCD risk, or a child. In all scenarios, a majority said that the chance genetic therapy would stop or slow progression, and risk of serious adverse and unintended effects, were important considerations. Qualitative analysis of free-text responses found that concern was often informed by family experience. Patient consideration of genetic therapy is likely to require individualized assessment of the benefits and risks.
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Eltzschig H, Ruan W, Li T, Lee J, Bang IH, Deng W, Ma X, Yoo SH, Kim B, Li J, Yuan X, An Y, Wang YY, Liang Y, Deberge M, Zhang D, Zhou Z, Wang Y, Gorham J, Seidman J, Seidman C, Aranki S, Nair R, Li L, Narula J, Zhao Z, Gorfe A, Muehlschlegel J, Tsai KL. The BMAL1/HIF2A heterodimer modulates circadian variations of myocardial injury. RESEARCH SQUARE 2024:rs.3.rs-3938716. [PMID: 38464103 PMCID: PMC10925443 DOI: 10.21203/rs.3.rs-3938716/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Acute myocardial infarction stands as a prominent cause of morbidity and mortality worldwide 1-6 . Clinical studies have demonstrated that the severity of cardiac injury following myocardial infarction exhibits a circadian pattern, with larger infarct sizes and poorer outcomes in patients experiencing morning onset myocardial infarctions 7-14 . However, the molecular mechanisms that govern circadian variations of myocardial injury remain unclear. Here, we show that BMAL1 14-20 , a core circadian transcription factor, orchestrates diurnal variability in myocardial injury. Unexpectedly, BMAL1 modulates circadian-dependent cardiac injury by forming a transcriptionally active heterodimer with a non-canonical partner, hypoxia-inducible factor 2 alpha (HIF2A) 6,21-23 , in a diurnal manner. Substantiating this finding, we determined the cryo-EM structure of the BMAL1/HIF2A/DNA complex, revealing a previously unknown capacity for structural rearrangement within BMAL1, which enables the crosstalk between circadian rhythms and hypoxia signaling. Furthermore, we identified amphiregulin (AREG) as a rhythmic transcriptional target of the BMAL1/HIF2A heterodimer, critical for regulating circadian variations of myocardial injury. Finally, pharmacologically targeting the BMAL1/HIF2A-AREG pathway provides effective cardioprotection, with maximum efficacy when aligned with the pathway's circadian trough. Our findings not only uncover a novel mechanism governing the circadian variations of myocardial injury but also pave the way for innovative circadian-based treatment strategies, potentially shifting current treatment paradigms for myocardial infarction.
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Yu M, Aguirre M, Jia M, Gjoni K, Cordova-Palomera A, Munger C, Amgalan D, Ma XR, Pereira A, Tcheandjieu C, Seidman C, Seidman J, Tristani-Firouzi M, Chung W, Goldmuntz E, Srivastava D, Loos RJ, Chami N, Cordell H, Dreßen M, Mueller-Myhsok B, Lahm H, Krane M, Pollard KS, Engreitz JM, Gagliano Taliun SA, Gelb BD, Priest JR. Oligogenic Architecture of Rare Noncoding Variants Distinguishes 4 Congenital Heart Disease Phenotypes. CIRCULATION. GENOMIC AND PRECISION MEDICINE 2023; 16:258-266. [PMID: 37026454 PMCID: PMC10330096 DOI: 10.1161/circgen.122.003968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 01/29/2023] [Indexed: 05/10/2023]
Abstract
BACKGROUND Congenital heart disease (CHD) is highly heritable, but the power to identify inherited risk has been limited to analyses of common variants in small cohorts. METHODS We performed reimputation of 4 CHD cohorts (n=55 342) to the TOPMed reference panel (freeze 5), permitting meta-analysis of 14 784 017 variants including 6 035 962 rare variants of high imputation quality as validated by whole genome sequencing. RESULTS Meta-analysis identified 16 novel loci, including 12 rare variants, which displayed moderate or large effect sizes (median odds ratio, 3.02) for 4 separate CHD categories. Analyses of chromatin structure link 13 of the genome-wide significant loci to key genes in cardiac development; rs373447426 (minor allele frequency, 0.003 [odds ratio, 3.37 for Conotruncal heart disease]; P=1.49×10-8) is predicted to disrupt chromatin structure for 2 nearby genes BDH1 and DLG1 involved in Conotruncal development. A lead variant rs189203952 (minor allele frequency, 0.01 [odds ratio, 2.4 for left ventricular outflow tract obstruction]; P=1.46×10-8) is predicted to disrupt the binding sites of 4 transcription factors known to participate in cardiac development in the promoter of SPAG9. A tissue-specific model of chromatin conformation suggests that common variant rs78256848 (minor allele frequency, 0.11 [odds ratio, 1.4 for Conotruncal heart disease]; P=2.6×10-8) physically interacts with NCAM1 (PFDR=1.86×10-27), a neural adhesion molecule acting in cardiac development. Importantly, while each individual malformation displayed substantial heritability (observed h2 ranging from 0.26 for complex malformations to 0.37 for left ventricular outflow tract obstructive disease) the risk for different CHD malformations appeared to be separate, without genetic correlation measured by linkage disequilibrium score regression or regional colocalization. CONCLUSIONS We describe a set of rare noncoding variants conferring significant risk for individual heart malformations which are linked to genes governing cardiac development. These results illustrate that the oligogenic basis of CHD and significant heritability may be linked to rare variants outside protein-coding regions conferring substantial risk for individual categories of cardiac malformation.
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Reichart D, Newby GA, Wakimoto H, Lun M, Gorham JM, Curran JJ, Raguram A, DeLaughter DM, Conner DA, Marsiglia JDC, Kohli S, Chmatal L, Page DC, Zabaleta N, Vandenberghe L, Liu DR, Seidman JG, Seidman C. Efficient in vivo genome editing prevents hypertrophic cardiomyopathy in mice. Nat Med 2023; 29:412-421. [PMID: 36797483 PMCID: PMC9941048 DOI: 10.1038/s41591-022-02190-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 12/16/2022] [Indexed: 02/18/2023]
Abstract
Dominant missense pathogenic variants in cardiac myosin heavy chain cause hypertrophic cardiomyopathy (HCM), a currently incurable disorder that increases risk for stroke, heart failure and sudden cardiac death. In this study, we assessed two different genetic therapies-an adenine base editor (ABE8e) and a potent Cas9 nuclease delivered by AAV9-to prevent disease in mice carrying the heterozygous HCM pathogenic variant myosin R403Q. One dose of dual-AAV9 vectors, each carrying one half of RNA-guided ABE8e, corrected the pathogenic variant in ≥70% of ventricular cardiomyocytes and maintained durable, normal cardiac structure and function. An additional dose provided more editing in the atria but also increased bystander editing. AAV9 delivery of RNA-guided Cas9 nuclease effectively inactivated the pathogenic allele, albeit with dose-dependent toxicities, necessitating a narrow therapeutic window to maintain health. These preclinical studies demonstrate considerable potential for single-dose genetic therapies to correct or silence pathogenic variants and prevent the development of HCM.
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Zhang Q, Kim SW, Gorham JM, DeLaughter D, Ward T, Seidman C, Seidman J. Multiplexed Single-Nucleus RNA Sequencing Using Lipid-Oligo Barcodes. Curr Protoc 2022; 2:e579. [PMID: 36286606 PMCID: PMC9614549 DOI: 10.1002/cpz1.579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This protocol describes a robust pipeline for simultaneously analyzing multiple samples by single-nucleus (sn)RNA-seq. cDNA obtained from each single sample are labeled with the same lipid-coupled oligonucleotide barcode (10X Genomics). Nuclei from as many as 12 individual samples can be pooled together and simultaneously processed for cDNA library construction and subsequent DNA sequencing. While previous protocols using lipid-coupled oligonucleotide barcodes were optimized for analysis of samples consisting of viable cells, this protocol is optimized for analyses of quick-frozen cell samples. The protocol ensures efficient recovery of nuclei both by incorporating high sucrose buffered solutions and by including a tracking dye (trypan blue) during nuclei isolation. The protocol also describes a procedure for removing single nuclei 'artifacts' by removing cell debris prior to single nuclear fractionation. This protocol informs the use of computational tools for filtering poorly labeled nuclei and assigning sample identity using barcode unique molecular identifier (UMI) read counts percentages. The computational pipeline is applicable to either cultured or primary, fresh or frozen cells, regardless of their cell types and species. Overall, this protocol reduces batch effects and experimental costs while enhancing sample comparison. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Labeling cells with lipid oligo barcodes and generating multiplexed single-nucleus RNA-seq libraries Basic Protocol 2: Bioinformatic deconvolution of the multiplexed snRNAseq libraries.
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Zhang H, Jamieson KL, Grenier J, Nikhanj A, Tang J, Wang F, Wang S, Seidman J, Seidman C, Thompson R, Seubert J, Oudit G. Demystifying Cardiac Iron Deficiency in End‐stage Heart Failure. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.0r588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Taub MA, Conomos MP, Keener R, Iyer KR, Weinstock JS, Yanek LR, Lane J, Miller-Fleming TW, Brody JA, Raffield LM, McHugh CP, Jain D, Gogarten SM, Laurie CA, Keramati A, Arvanitis M, Smith AV, Heavner B, Barwick L, Becker LC, Bis JC, Blangero J, Bleecker ER, Burchard EG, Celedón JC, Chang YPC, Custer B, Darbar D, de las Fuentes L, DeMeo DL, Freedman BI, Garrett ME, Gladwin MT, Heckbert SR, Hidalgo BA, Irvin MR, Islam T, Johnson WC, Kaab S, Launer L, Lee J, Liu S, Moscati A, North KE, Peyser PA, Rafaels N, Seidman C, Weeks DE, Wen F, Wheeler MM, Williams LK, Yang IV, Zhao W, Aslibekyan S, Auer PL, Bowden DW, Cade BE, Chen Z, Cho MH, Cupples LA, Curran JE, Daya M, Deka R, Eng C, Fingerlin TE, Guo X, Hou L, Hwang SJ, Johnsen JM, Kenny EE, Levin AM, Liu C, Minster RL, Naseri T, Nouraie M, Reupena MS, Sabino EC, Smith JA, Smith NL, Lasky-Su J, Taylor JG, Telen MJ, Tiwari HK, Tracy RP, White MJ, Zhang Y, Wiggins KL, Weiss ST, Vasan RS, Taylor KD, Sinner MF, Silverman EK, Shoemaker MB, Sheu WHH, Sciurba F, Schwartz DA, Rotter JI, Roden D, Redline S, Raby BA, Psaty BM, Peralta JM, Palmer ND, Nekhai S, Montgomery CG, Mitchell BD, Meyers DA, McGarvey ST, Mak AC, Loos RJ, Kumar R, Kooperberg C, Konkle BA, Kelly S, Kardia SL, Kaplan R, He J, Gui H, Gilliland FD, Gelb BD, Fornage M, Ellinor PT, de Andrade M, Correa A, Chen YDI, Boerwinkle E, Barnes KC, Ashley-Koch AE, Arnett DK, Albert C, Laurie CC, Abecasis G, Nickerson DA, Wilson JG, Rich SS, Levy D, Ruczinski I, Aviv A, Blackwell TW, Thornton T, O’Connell J, Cox NJ, Perry JA, Armanios M, Battle A, Pankratz N, Reiner AP, Mathias RA. Genetic determinants of telomere length from 109,122 ancestrally diverse whole-genome sequences in TOPMed. CELL GENOMICS 2022; 2:S2666-979X(21)00105-1. [PMID: 35530816 PMCID: PMC9075703 DOI: 10.1016/j.xgen.2021.100084] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 09/03/2021] [Accepted: 12/10/2021] [Indexed: 01/16/2023]
Abstract
Genetic studies on telomere length are important for understanding age-related diseases. Prior GWAS for leukocyte TL have been limited to European and Asian populations. Here, we report the first sequencing-based association study for TL across ancestrally-diverse individuals (European, African, Asian and Hispanic/Latino) from the NHLBI Trans-Omics for Precision Medicine (TOPMed) program. We used whole genome sequencing (WGS) of whole blood for variant genotype calling and the bioinformatic estimation of telomere length in n=109,122 individuals. We identified 59 sentinel variants (p-value <5×10-9) in 36 loci associated with telomere length, including 20 newly associated loci (13 were replicated in external datasets). There was little evidence of effect size heterogeneity across populations. Fine-mapping at OBFC1 indicated the independent signals colocalized with cell-type specific eQTLs for OBFC1 (STN1). Using a multi-variant gene-based approach, we identified two genes newly implicated in telomere length, DCLRE1B (SNM1B) and PARN. In PheWAS, we demonstrated our TL polygenic trait scores (PTS) were associated with increased risk of cancer-related phenotypes.
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Ward T, Tai W, Morton S, Impens F, Van Damme P, Van Haver D, Timmerman E, Venturini G, Zhang K, Jang MY, Willcox JAL, Haghighi A, Gelb BD, Chung WK, Goldmuntz E, Porter GA, Lifton RP, Brueckner M, Yost HJ, Bruneau BG, Gorham J, Kim Y, Pereira A, Homsy J, Benson CC, DePalma SR, Varland S, Chen CS, Arnesen T, Gevaert K, Seidman C, Seidman JG. Mechanisms of Congenital Heart Disease Caused by NAA15 Haploinsufficiency. Circ Res 2021; 128:1156-1169. [PMID: 33557580 PMCID: PMC8048381 DOI: 10.1161/circresaha.120.316966] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
[Figure: see text].
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Elisofon SA, Magee JC, Ng VL, Horslen SP, Fioravanti V, Economides J, Erinjeri J, Anand R, Mazariegos GV, Martin A, Mannino D, Flynn L, Mohammad S, Alonso E, Superina R, Brandt K, Riordan M, Lokar J, Ito J, Elisofon S, Zapata L, Jain A, Foristal E, Gupta N, Whitlow C, Naik K, Espinosa H, Miethke A, Hawkins A, Hardy J, Engels E, Schreibeis A, Ovchinsky N, Kogan‐Liberman D, Cunningham R, Malik P, Sundaram S, Feldman A, Garcia B, Yanni G, Kohli R, Emamaullee J, Secules C, Magee J, Lopez J, Bilhartz J, Hollenbeck J, Shaw B, Bartow C, Forest S, Rand E, Byrne A, Linguiti I, Wann L, Seidman C, Mazariegos G, Soltys K, Squires J, Kepler A, Vitola B, Telega G, Lerret S, Desai D, Moghe J, Cutright L, Daniel J, Andrews W, Fioravanti V, Slowik V, Cisneros R, Faseler M, Hufferd M, Kelly B, Sudan D, Mavis A, Moats L, Swan‐Nesbit S, Yazigi N, Buranych A, Hobby A, Rao G, Maccaby B, Gopalareddy V, Boulware M, Ibrahim S, El Youssef M, Furuya K, Schatz A, Weckwerth J, Lovejoy C, Kasi N, Nadig S, Law M, Arnon R, Chu J, Bucuvalas J, Czurda M, Secheli B, Almy C, Haydel B, Lobritto S, Emand J, Biney‐Amissah E, Gamino D, Gomez A, Himes R, Seal J, Stewart S, Bergeron J, Truxillo A, Lebel S, Davidson H, Book L, Ramstack D, Riley A, Jennings C, Horslen S, Hsu E, Wallace K, Turmelle Y, Nadler M, Postma S, Miloh T, Economides J, Timmons K, Ng V, Subramonian A, Dharmaraj B, McDiarmid S, Feist S, Rhee S, Perito E, Gallagher L, Smith K, Ebel N, Zerofsky M, Nogueira J, Greer R, Gilmour S, Robert C, Cars C, Azzam R, Boone P, Garbarino N, Lalonde M, Kerkar N, Dokus K, Helbig K, Grizzanti M, Tomiyama K, Cocking J, Alexopoulos S, Bhave C, Schillo R, Bailey A, Dulek D, Ramsey L, Ekong U, Valentino P, Hettiarachchi D, Tomlin R. Society of pediatric liver transplantation: Current registry status 2011-2018. Pediatr Transplant 2020; 24:e13605. [PMID: 31680409 DOI: 10.1111/petr.13605] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/08/2019] [Accepted: 09/27/2019] [Indexed: 11/29/2022]
Abstract
BACKGROUND SPLIT was founded in 1995 in order to collect comprehensive prospective data on pediatric liver transplantation, including waiting list data, transplant, and early and late outcomes. Since 2011, data collection of the current registry has been refined to focus on prospective data and outcomes only after transplant to serve as a foundation for the future development of targeted clinical studies. OBJECTIVE To report the outcomes of the SPLIT registry from 2011 to 2018. METHODS This is a multicenter, cross-sectional analysis characterizing patients transplanted and enrolled in the SPLIT registry between 2011 and 2018. All patients, <18 years of age, received a first liver-only, a combined liver-kidney, or a combined liver-pancreas transplant during this study period. RESULTS A total of 1911 recipients from 39 participating centers in North America were registered. Indications included biliary atresia (38.5%), metabolic disease (19.1%), tumors (11.7%), and fulminant liver failure (11.5%). Greater than 50% of recipients were transplanted as either Status 1A/1B or with a MELD/PELD exception score. Incompatible transplants were performed in 4.1%. Kaplan-Meier estimates of 1-year patient and graft survival were 97.3% and 96.6%. First 30 days of surgical complications included reoperation (31.7%), hepatic artery thrombosis (6.3%), and portal vein thrombosis (3.2%). In the first 90 days, biliary tract complications were reported in 13.6%. Acute cellular rejection during first year was 34.7%. At 1 and 2 years of follow-up, 39.2% and 50.6% had normal liver tests on monotherapy (tacrolimus or sirolimus). Further surgical, survival, allograft function, and complications are detailed.
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10
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Fahed A, Nemer G, Bitar F, Arnaout S, Abche A, Ware J, Batrawi M, Khalil A, DePalma S, McDonough B, Arabi M, Seidman J, Seidman C. Abstract 202: The R21C Mutation in Troponin I Has a Founder Effect in South Lebanon and Causes Malignant Hypertrophic Cardiomyopathy. Circ Res 2019. [DOI: 10.1161/res.125.suppl_1.202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hypertrophic Cardiomyopathy (HCM) occurs in 1 of every 500 people and has a wide phenotypic variability. In the majority of cases, HCM is caused by known mutations in genes that code for sarcomere proteins. Although gene testing is widely available for HCM, knowing the phenotype caused by different gene mutations remains a challenging task. We recruited 28 families with HCM, of which 19 (67.8%) have at least one patient with pediatric onset. Index patients from 20 families received targeted sequencing for a panel of genes including
TNNI3
, and 7 families received Sanger sequencing for the
TNNI3
. We identified a missense mutation p.R21C in
TNNI3
segregating with HCM in four families from South Lebanon. Through cascade screening, we identified 30 patients from the four families; twenty of them (67%) had a clinical diagnosis of HCM with a median age of 37 years, while 9 (30%), with a median age 21 years, had no evidence of HCM on echocardiography. An additional 27 members of the families had evidence of HCM, including 22 with SCD in the setting of no past medical history, and their carrier status for p.R21C was implied from the pedigrees. Survival analysis for 57 HCM patients with the mutation revealed a markedly decreased age at first adverse event as compared to 47 HCM patients with the
MYBPC3
p.R502W mutation. Founder mutations in HCM that cause a severe phenotype are uncommon. The p.R21C mutation in
TNNI3
is the first HCM mutation described in the Lebanese population and has a founder effect in South Lebanon. Early and more frequent screening with different imaging modalities as well as tailored management might be warranted for carriers of this mutation.
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Toepfer C, Sharma A, Garfinkel A, Cicconet M, Agarwal R, Chopra A, Chen C, Seidman J, Seidman C. Abstract 341: Efficient Large-scale Sarcomere Tracking (sarctrack) to Assess HCM Variants in iPSC-CMs. Circ Res 2019. [DOI: 10.1161/res.125.suppl_1.341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Variants that drive HCM and associated adverse patient outcomes are found in the cardiac sarcomere. These variants range from those that are known to be pathogenic to those that are likely pathogenic or even variants of unknown significance (VUS). CRISPR/Cas-9 engineering has accelerated our ability to generate variants in iPSC to probe changes in cellular function and assess cellular pathogenicity in VUSs. However, iPSC-CMs are not as functionally mature as adult cardiomyocytes. For this reason we have developed a platform to assess contractile function directly at the level of the sarcomere. We use a custom built MatLab algorithm to assess sarcomere length, contraction time, relaxation time, and beat rate of individual sarcomeres within iPSC-CMs. Sarcomeres are visualised using reporter lines that have been engineered with an N-terminal TTN-GFP. We assess the contractile function of thick filament variants in MYH7 and MYBPC3. We show the ability to detect changes in key contractile parameters. This platform allows the screening of pharmacological compounds against these reporter lines with engineered variants.
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Adalsteinsdottir B, Ho C, Burke M, Danielsen R, Maron B, Seidman J, Seidman C, Gunnarsson G. DIASTOLIC FUNCTION IN MYOSIN-BINDING PROTEIN C FOUNDER MUTATION CARRIERS WITH AND WITHOUT CLINICAL EVIDENCE OF HYPERTROPHIC CARDIOMYOPATHY. J Am Coll Cardiol 2019. [DOI: 10.1016/s0735-1097(19)31538-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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13
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Williams LK, Misurka J, Ho CY, Chan WX, Agmon Y, Seidman C, Rakowski H, Carasso S. Multilayer Myocardial Mechanics in Genotype-Positive Left Ventricular Hypertrophy-Negative Patients With Hypertrophic Cardiomyopathy. Am J Cardiol 2018; 122:1754-1760. [PMID: 30249441 DOI: 10.1016/j.amjcard.2018.08.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 07/30/2018] [Accepted: 08/02/2018] [Indexed: 11/19/2022]
Abstract
It is unknown whether the presence of a sarcomeric mutation alone is sufficient to result in abnormal myocardial force generation, or whether additional changes in myocardial architecture (hypertrophy, disarray, and fibrosis) are required to impair systolic function. Speckle tracking echocardiography allows quantification of global strain/strain rates, twist, and dyssynchrony. In the present study we sought to further elucidate early abnormalities of myocardial mechanics in sarcomeric mutation carriers without evidence of clinical disease. Sixty genotype-positive left ventricular hypertrophy-negative (G+left ventricular hypertrophy [LVH]-) patients and 60 normal controls were studied. Velocity vector imaging was applied retrospectively to echocardiographic images to quantify global longitudinal and circumferential strain/strain rate, and rotation parameters. The G+LVH- group demonstrated both smaller left ventricular diastolic cavity dimensions (4.5 ± 0.6 cm vs 4.8 ± 0.4 cm) and a higher LVEF (66 ± 6% vs 60 ± 5%) compared with controls. An increase in circumferential subendocardial systolic strain (-30 ± 5 vs -27 ± 3%) and both systolic and diastolic subendocardial strain rate was seen in the G+LVH- group. Peak rotation angles were higher at the base and apex, with an increase in total twist (9.0 ± 3.8 vs 6.9 ± 2.9). In the control group, global and average segmental strain were similar, suggesting no/minimal dyssynchrony (global mechanical synchrony index [GMSi] 0.97-0.98). In the G+LVH- group GMSi was significantly lower (subendocardial GMSi 0.95; subepicardial GMSi 0.60), suggesting increasing subendocardial to subepicardial dyssynchrony. In conclusion, utilizing multilayer strain analysis, we demonstrate that G+LVH- subjects have enhanced subendocardial systolic strain rate and twist, as well as mechanical dyssynchrony within the left ventricular myocardium. These results demonstrate that abnormalities in myocardial mechanics precede the development of clinical hypertrophy.
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Toepfer CN, Wakimoto H, Garfinkel AC, McDonough B, Liao D, Jiang J, Tai A, Gorham J, Lund IG, Lund IG, Lun M, Lynch TL, Sadayappan S, Redwood CS, Watkins H, Seidman J, Seidman C. Abstract 571:
MYBPC3
Mutations Cause Hypertrophic Cardiomyopathy by Dysregulating Myosin: Implications for Therapy. Circ Res 2018. [DOI: 10.1161/res.123.suppl_1.571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The mechanisms by which truncating mutations in
MYBPC3
(encoding cardiac myosin binding protein-C; cMyBPC) or myosin missense mutations cause hyper-contractility and poor relaxation in hypertrophic cardiomyopathy (HCM) are incompletely understood. Using genetic and biochemical approaches we explored how depletion of cMyBPC altered sarcomere function. We demonstrate that stepwise loss of cMyBPC resulted in reciprocal augmentation of myosin contractility. Direct attenuation of myosin function, via a damaging missense variant (F764L) that causes dilated cardiomyopathy (DCM) normalized the increased contractility from cMyBPC depletion. Depletion of cMyBPC also altered dynamic myosin conformations during relaxation - enhancing the myosin state that enables ATP hydrolysis and thin filament interactions while reducing the super relaxed conformation associated with energy conservation. MYK-461, a pharmacologic inhibitor of myosin ATPase, rescued relaxation deficits and restored normal contractility in mouse and human cardiomyocytes with
MYBPC3
mutations. These data define dosage-dependent effects of cMyBPC on myosin that occur across all phases of the cardiac cycle as the pathophysiologic mechanisms by which
MYBPC3
truncations cause HCM. Therapeutic strategies to attenuate cMyBPC activity may rescue depressed cardiac contractility in DCM patients, while inhibiting myosin by MYK-461 should benefit the substantial proportion of HCM patients with
MYBPC3
mutations.
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Manolio TA, Fowler DM, Starita LM, Haendel MA, MacArthur DG, Biesecker LG, Worthey E, Chisholm RL, Green ED, Jacob HJ, McLeod HL, Roden D, Rodriguez LL, Williams MS, Cooper GM, Cox NJ, Herman GE, Kingsmore S, Lo C, Lutz C, MacRae CA, Nussbaum RL, Ordovas JM, Ramos EM, Robinson PN, Rubinstein WS, Seidman C, Stranger BE, Wang H, Westerfield M, Bult C. Bedside Back to Bench: Building Bridges between Basic and Clinical Genomic Research. Cell 2017; 169:6-12. [PMID: 28340351 DOI: 10.1016/j.cell.2017.03.005] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Genome sequencing has revolutionized the diagnosis of genetic diseases. Close collaborations between basic scientists and clinical genomicists are now needed to link genetic variants with disease causation. To facilitate such collaborations, we recommend prioritizing clinically relevant genes for functional studies, developing reference variant-phenotype databases, adopting phenotype description standards, and promoting data sharing.
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Fahed AC, Candan Ş, Haghighi A, DePalma S, McDonough B, Erer B, Ekmekçi A, Bornaun H, Öztarhan K, Aydin H, Seidman J, Seidman C. PEDIATRIC CARDIOMYOPATHY MUTATIONS IN A HIGHLY CONSANGUINEOUS POPULATION. J Am Coll Cardiol 2016. [DOI: 10.1016/s0735-1097(16)31400-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Hool LC, Viola HM, Johnstone VP, Cserne Szappanos H, Tsoutsman T, Semsarian C, Seidman C. Characterising the Effects of a Peptide Directed Against the L-Type Ca2+ Channel on Mitochondrial Function in Hypertrophic Cardiomyopathy. Biophys J 2016. [DOI: 10.1016/j.bpj.2015.11.2417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Roberts AM, Ware J, Herman D, Schafer S, Mazzarotto F, Baksi J, Buchan R, Walsh R, John S, Wilkinson S, Felkin L, Bick A, Radke M, Gotthardt M, Barton P, Hubner N, Seidman J, Seidman C, Cook S. C Integrated Allelic, Transcriptional, and Phenotypic Dissection of the Cardiac Effects of Titin Variation in Health and Diseaser. BRITISH HEART JOURNAL 2015. [DOI: 10.1136/heartjnl-2015-308066.232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Roberts A, Ware J, Herman D, Schafer S, Mazzarotto F, Baksi J, Buchan R, Walsh R, John S, Wilkinson S, Felkin L, Bick A, Radke M, Gotthardt M, Barton P, Hubner N, Seidman J, Seidman C, Cook S. 163 Integrated allelic, transcriptional, and phenotypic dissection of the cardiac effects of titin variation in health and disease. BRITISH HEART JOURNAL 2015. [DOI: 10.1136/heartjnl-2015-308066.163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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20
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García-Giustiniani D, Arad M, Ortíz-Genga M, Barriales-Villa R, Fernández X, Rodríguez-García I, Mazzanti A, Veira E, Maneiro E, Rebolo P, Lesende I, Cazón L, Freimark D, Gimeno-Blanes JR, Seidman C, Seidman J, McKenna W, Monserrat L. Phenotype and prognostic correlations of the converter region mutations affecting the β myosin heavy chain. Heart 2015; 101:1047-53. [PMID: 25935763 PMCID: PMC4484257 DOI: 10.1136/heartjnl-2014-307205] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 03/30/2015] [Indexed: 12/01/2022] Open
Abstract
Objectives The prognostic value of genetic studies in cardiomyopathies is still controversial. Our objective was to evaluate the outcome of patients with cardiomyopathy with mutations in the converter domain of β myosin heavy chain (MYH7). Methods Clinical characteristics and survival of 117 affected members with mutations in the converter domain of MYH7 were compared with 409 patients described in the literature with mutations in the same region. Results Twenty-five mutations were evaluated (9 in our families including 3 novel (Ile730Asn, Asp717Gly and Arg719Pro)). Clinical diagnoses were hypertrophic (n=407), dilated (n=15), non-compaction (n=4) and restrictive (n=5) cardiomyopathies, unspecified cardiomyopathy (n=11), sudden death (n=50) and 35 healthy carriers. One hundred eighty-four had events (cardiovascular death or transplant). Median event-free survival was 50±2 years in our patients and 53±3 years in the literature (p=0.27). There were significant differences in the outcome between mutation: Ile736Thr had fewer events than other mutations in the region (p=0.01), while Arg719Gln (p<0.01) had reduced event-free survival. Conclusions Mutations in the converter region are generally associated with adverse prognosis although there are differences between mutations. The identification of a mutation in this particular region provides important prognostic information that should be considered in the clinical management of affected patients.
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Seidman C. Genetic Pathways in Congenital Heart Development. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.215.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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22
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Fahed A, Nemer G, Bitar FF, Arnaout S, Abchee AB, Ware J, Batrawi M, DePalma SR, McDonough B, Arabi MT, Seidman J, Seidman C. THE R21C MUTATION IN TROPONIN I HAS A FOUNDER EFFECT IN SOUTH LEBANON AND CAUSES MALIGNANT HYPERTROPHIC CARDIOMYOPATHY. J Am Coll Cardiol 2015. [DOI: 10.1016/s0735-1097(15)60958-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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23
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Viola H, Johnstone V, Cserne Szappanos H, Tsoutsman T, Semsarian C, Seidman C, Hool L. Characterising effects of a peptide directed against the L-type Ca2+ channel on mitochondrial function in hypertrophic cardiomyopathy. Heart Lung Circ 2015. [DOI: 10.1016/j.hlc.2015.06.153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Carethers JM, Coughlin S, Diamond B, Erzurum S, Fried LP, Jameson JL, Kaushansky K, Klotman ME, Lemon S, Mitchell B, Rothman P, Sawyers C, Seidman C, Somlo S. The imperative to invest in science has never been greater. J Clin Invest 2014. [DOI: 10.1172/jci79469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Glessner JT, Bick AG, Ito K, Homsy J, Rodriguez-Murillo L, Fromer M, Mazaika E, Vardarajan B, Italia M, Leipzig J, DePalma SR, Golhar R, Sanders SJ, Yamrom B, Ronemus M, Iossifov I, Willsey AJ, State MW, Kaltman JR, White PS, Shen Y, Warburton D, Brueckner M, Seidman C, Goldmuntz E, Gelb BD, Lifton R, Seidman J, Hakonarson H, Chung WK. Increased frequency of de novo copy number variants in congenital heart disease by integrative analysis of single nucleotide polymorphism array and exome sequence data. Circ Res 2014; 115:884-896. [PMID: 25205790 DOI: 10.1161/circresaha.115.304458] [Citation(s) in RCA: 182] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
RATIONALE Congenital heart disease (CHD) is among the most common birth defects. Most cases are of unknown pathogenesis. OBJECTIVE To determine the contribution of de novo copy number variants (CNVs) in the pathogenesis of sporadic CHD. METHODS AND RESULTS We studied 538 CHD trios using genome-wide dense single nucleotide polymorphism arrays and whole exome sequencing. Results were experimentally validated using digital droplet polymerase chain reaction. We compared validated CNVs in CHD cases with CNVs in 1301 healthy control trios. The 2 complementary high-resolution technologies identified 63 validated de novo CNVs in 51 CHD cases. A significant increase in CNV burden was observed when comparing CHD trios with healthy trios, using either single nucleotide polymorphism array (P=7×10(-5); odds ratio, 4.6) or whole exome sequencing data (P=6×10(-4); odds ratio, 3.5) and remained after removing 16% of de novo CNV loci previously reported as pathogenic (P=0.02; odds ratio, 2.7). We observed recurrent de novo CNVs on 15q11.2 encompassing CYFIP1, NIPA1, and NIPA2 and single de novo CNVs encompassing DUSP1, JUN, JUP, MED15, MED9, PTPRE SREBF1, TOP2A, and ZEB2, genes that interact with established CHD proteins NKX2-5 and GATA4. Integrating de novo variants in whole exome sequencing and CNV data suggests that ETS1 is the pathogenic gene altered by 11q24.2-q25 deletions in Jacobsen syndrome and that CTBP2 is the pathogenic gene in 10q subtelomeric deletions. CONCLUSIONS We demonstrate a significantly increased frequency of rare de novo CNVs in CHD patients compared with healthy controls and suggest several novel genetic loci for CHD.
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