This work was supported by the Medical Research Fund project of Guangdong Province (A2022363) and the major project of the Guangdong Committee of Science and Technology, China (grant no.2022).
We would like to thank Qingjian Chen of the University of Maryland, College Park for the help during the preparation of this manuscript.

The histories of the families were obtained by interviewing the family members. The study was approved by the Ethics Committee of the Guangdong Provincial Hospital of Chinese Medicine (No. 2019074). Informed written consent was obtained from all the family members. All the animals are treated in accordance with the ethical guidelines of the Guangdong Provincial Hospital of Chinese Medicine (Guangzhou, China).
1. Study subjects
NOTE: The proband III-3 ...

<ol>
	<li>Toepfer, C. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Myosin+sequestration+regulates+sarcomere+function,+cardiomyocyte+energetics,+and+metabolism,+informing+the+pathogenesis+of+hypertrophic+cardiomyopathy.">Myosin sequestration regulates sarcomere function, cardiomyocyte energetics, and metabolism, informing the pathogenesis of hypertrophic cardiomyopathy.</a> Circulation. 141 (10), 828-842 (2020).</li><li>Writing Committee Members et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=2020+AHA/ACC+guideline+for+the+diagnosis+and+treatment+of+patients+with+hypertrophic+cardiomyopathy:+A+report+of+the+American+College+of+Cardiology/American+Heart+Association+Joint+Committee+on+Clinical+Practice+Guidelines.">2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy: A report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines.</a> The Journal of Thoracic and Cardiovascular Surgery. 162 (1), 23-106 (2021).</li><li>Elliott, P., McKenna, W. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypertrophic+cardiomyopathy.">Hypertrophic cardiomyopathy.</a> Lancet. 363 (9424), 1881-1891 (2004).</li><li>Maron, B. J., Maron, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypertrophic+cardiomyopathy.">Hypertrophic cardiomyopathy.</a> Lancet. 381 (9862), 242-255 (2013).</li><li>Inoue, T., Orgel, L. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+nonenzymatic+RNA+polymerase+model.">A nonenzymatic RNA polymerase model.</a> Science. 219 (4586), 859-862 (1983).</li><li>Sanger, F., Nicklen, S., Coulson, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DNA+sequencing+with+chain-terminating+inhibitors.">DNA sequencing with chain-terminating inhibitors.</a> Proceedings of the National Academy of Sciences of the United States of America. 74 (12), 5463-5467 (1977).</li><li>Sachidanandam, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+map+of+human+genome+sequence+variation+containing+1.42+million+single+nucleotide+polymorphisms.">A map of human genome sequence variation containing 1.42 million single nucleotide polymorphisms.</a> Nature. 409 (6822), 928-933 (2001).</li><li>Ng, S. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+capture+and+massively+parallel+sequencing+of+12+human+exomes.">Targeted capture and massively parallel sequencing of 12 human exomes.</a> Nature. 461 (7261), 272-276 (2009).</li><li>Wong, K. M., Hudson, T. J., McPherson, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Unraveling+the+genetics+of+cancer:+genome+sequencing+and+beyond.">Unraveling the genetics of cancer: genome sequencing and beyond.</a> Annual Review of Genomics and Human Genetics. 12, 407-430 (2011).</li><li>Mattivi, C. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+utility+of+a+phenotype-enhanced+MYH7-specific+variant+classification+framework+in+hypertrophic+cardiomyopathy+genetic+testing.">Clinical utility of a phenotype-enhanced MYH7-specific variant classification framework in hypertrophic cardiomyopathy genetic testing.</a> Circulation. Genomic and Precision Medicine. 13 (5), 453-459 (2020).</li><li>Jiang, J., Wakimoto, H., Seidman, J. G., Seidman, C. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Allele-specific+silencing+of+mutant+Myh6+transcripts+in+mice+suppresses+hypertrophic+cardiomyopathy.">Allele-specific silencing of mutant Myh6 transcripts in mice suppresses hypertrophic cardiomyopathy.</a> Science. 342 (6154), 111-114 (2013).</li><li>Hayashi, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+background+of+Japanese+patients+with+pediatric+hypertrophic+and+restrictive+cardiomyopathy.">Genetic background of Japanese patients with pediatric hypertrophic and restrictive cardiomyopathy.</a> Journal of Human Genetics. 63 (9), 989-996 (2018).</li><li>Gil, W. S., &#193;vila Vidal, L. A., V&#225;squez Salguero, M. A., Cajiao, M. B., Pe&#241;a, C. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+variant+affecting+the+myosin+light+chain+2+related+to+familial+hypertrophic+cardiomyopathy.">Genetic variant affecting the myosin light chain 2 related to familial hypertrophic cardiomyopathy.</a> Intractable &amp; Rare Diseases Research. 9 (4), 229-232 (2020).</li><li>Berge, K. E., Leren, T. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetics+of+hypertrophic+cardiomyopathy+in+Norway.">Genetics of hypertrophic cardiomyopathy in Norway.</a> Clinical Genetics. 86 (4), 355-360 (2014).</li><li>McNamara, J. W., Schuckman, M., Becker, R. C., Sadayappan, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+homozygous+intronic+variant+in+TNNT2+associates+with+feline+cardiomyopathy.">A novel homozygous intronic variant in TNNT2 associates with feline cardiomyopathy.</a> Frontiers in Physiology. 11, 608473 (2020).</li><li>Wang, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+transcriptome+analysis+of+atrial+septal+defect+identifies+dysregulated+genes+during+heart+septum+morphogenesis.">Comparative transcriptome analysis of atrial septal defect identifies dysregulated genes during heart septum morphogenesis.</a> Gene. 575, 303-312 (2016).</li><li>Andersen, P. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diagnostic+yield,+interpretation,+and+clinical+utility+of+mutation+screening+of+sarcomere+encoding+genes+in+Danish+hypertrophic+cardiomyopathy+patients+and+relatives.">Diagnostic yield, interpretation, and clinical utility of mutation screening of sarcomere encoding genes in Danish hypertrophic cardiomyopathy patients and relatives.</a> Human Mutations. 30 (3), 363-370 (2009).</li><li>Nakashima, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lifelong+clinical+impact+of+the+presence+of+sarcomere+gene+mutation+in+Japanese+patients+with+hypertrophic+cardiomyopathy.">Lifelong clinical impact of the presence of sarcomere gene mutation in Japanese patients with hypertrophic cardiomyopathy.</a> Circulation Journal. 84 (10), 1846-1853 (2020).</li><li>Hu, L. R., Kontrogianni-Konstantopoulos, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Proteomic+analysis+of+myocardia+containing+the+Obscurin+R4344Q+mutation+linked+to+hypertrophic+cardiomyopathy.">Proteomic analysis of myocardia containing the Obscurin R4344Q mutation linked to hypertrophic cardiomyopathy.</a> Frontiers in Physiology. 11, 478 (2020).</li><li>Girolami, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+alpha-actinin+2+variant+associated+with+familial+hypertrophic+cardiomyopathy+and+juvenile+atrial+arrhythmias:+a+massively+parallel+sequencing+study.">Novel alpha-actinin 2 variant associated with familial hypertrophic cardiomyopathy and juvenile atrial arrhythmias: a massively parallel sequencing study.</a> Circulation. Cardiovascular Genetics. 7 (6), 741-750 (2014).</li><li>Salazar-Mendiguchia, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+p.(Cys150Tyr)+variant+in+CSRP3+is+associated+with+late-onset+hypertrophic+cardiomyopathy+in+heterozygous+individuals.">The p.(Cys150Tyr) variant in CSRP3 is associated with late-onset hypertrophic cardiomyopathy in heterozygous individuals.</a> European Journal of Medical Genetics. 63 (12), 104079 (2020).</li><li>Teekakirikul, P., Zhu, W., Huang, H. C., Fung, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypertrophic+cardiomyopathy:+An+overview+of+genetics+and+management.">Hypertrophic cardiomyopathy: An overview of genetics and management.</a> Biomolecules. 9 (12), 878 (2019).</li><li>Crossley, B. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Guidelines+for+Sanger+sequencing+and+molecular+assay+monitoring.">Guidelines for Sanger sequencing and molecular assay monitoring.</a> Journal of Veterinary Diagnostic Investigation. 32 (6), 767-775 (2020).</li><li>Song, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mutations+profile+in+Chinese+patients+with+hypertrophic+cardiomyopathy.">Mutations profile in Chinese patients with hypertrophic cardiomyopathy.</a> Clinica Chimica Acta. 351 (1-2), 209-216 (2005).</li><li>Marian, A. J., Braunwald, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypertrophic+cardiomyopathy:+Genetics,+pathogenesis,+clinical+manifestations,+diagnosis,+and+therapy.">Hypertrophic cardiomyopathy: Genetics, pathogenesis, clinical manifestations, diagnosis, and therapy.</a> Circulation Research. 121 (7), 749-770 (2017).</li><li>Cann, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phenotype-driven+molecular+autopsy+for+sudden+cardiac+death.">Phenotype-driven molecular autopsy for sudden cardiac death.</a> Clinical Genetics. 91 (1), 22-29 (2017).</li><li>Lafreniere-Roula, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Family+screening+for+hypertrophic+cardiomyopathy:+Is+it+time+to+change+practice+guidelines.">Family screening for hypertrophic cardiomyopathy: Is it time to change practice guidelines.</a> European Heart Journal. 40 (45), 3672-3681 (2019).</li><li>Winkelmann, D. A., Forgacs, E., Miller, M. T., Stock, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+basis+for+drug-induced+allosteric+changes+to+human+beta-cardiac+myosin+motor+activity.">Structural basis for drug-induced allosteric changes to human beta-cardiac myosin motor activity.</a> Nature Communications. 6, 7974 (2015).</li><li>Garc&#237;a-Giustiniani, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phenotype+and+prognostic+correlations+of+the+converter+region+mutations+affecting+the+&#946;+myosin+heavy+chain.">Phenotype and prognostic correlations of the converter region mutations affecting the &#946; myosin heavy chain.</a> Heart (British Cardiac Society). 101 (13), 1047-1053 (2015).</li><li>Moore, J. R., Leinwand, L., Warshaw, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Understanding+cardiomyopathy+phenotypes+based+on+the+functional+impact+of+mutations+in+the+myosin+motor.">Understanding cardiomyopathy phenotypes based on the functional impact of mutations in the myosin motor.</a> Circulation Research. 111 (3), 375-385 (2012).</li><li>Majewski, J., Schwartzentruber, J., Lalonde, E., Montpetit, A., Jabado, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=What+can+exome+sequencing+do+for+you.">What can exome sequencing do for you.</a> Journal of Medical Genetics. 48 (9), 580-589 (2011).</li></ol>

The authors have no financial conflicts of interest to declare.

In this study, we describe one Chinese Han families with HCM. Genetics analysis revealed that a heterozygous MYH6 mutation p.G823E co-segregates with the disease in family members with autosomal dominant inheritance. To validate the pathogenicity of G823E mutation and discuss the underlying mechanisms, we created a C57BL/6N mouse model with G823E at mouse Myh7 locus by CRISPR/Cas9-mediated genome engineering.
Phenotypic characteristics of C57BL/6N-Myh7em1(G823E) knockin mice were ev...

Hypertrophic cardiomyopathy (HCM, OMIM: 613690) is the most common cardiomyopathy in China, with an estimated incidence of 0.2%, affecting 150,000 people1,2.
The pathological anatomical feature that characterizes HCM is asymmetric ventricular hypertrophy, which often involves the ventricular outflow tract and/or interventricular septum3. The clinical manifestation is exertional dyspnea, fatigue, and chest pain. The individual phenotype of HCM has variability ranging from clinically insidious to severe heart failure. Patients with HCM require medical treatment, heart transplantation, life support equipment, and multidisciplinary follow-up4.
In the past century, PCR technology has changed the way we study DNA5. A DNA sequencing method for clinical diagnosis was discovered by Sanger and colleagues6. The Sanger technique was subsequently applied to the Human Genome Project, but this approach was costly and time-consuming7. The advent of whole-genome sequencing (WGS) brought insights into human genetic disease to new heights, but it remained prohibitive in terms of cost. Whole-exome sequencing (WES) technology has long been used to detect germline variants8 and has been successful in identifying somatic driver mutations in the exome of various cancers9. The detection of DNA exons or coding regions by WES can be used to reveal pathogenic variants in most Mendelian diseases. Today, with the decreasing cost of sequencing, WGS is expected to become an important tool in genomics research and can be widely used in the detection of pathogenic variants in the genome.
WES technology has also been used in inherited cardiomyopathy to identify pathogenic variants to further elucidate the etiology. Emerging evidence has implicated that genes coding sarcomere structural protein gene mutations, such as MYH710, MYH611, MYBPC312, MYL213, MYL314, TNNT215, TNNI316, TNNC117, and TPM118 are responsible for the genetic etiology of HCM. Awareness of pathogenic variants in rare disease-causing genes (e.g., obscurin, cytoskeletal calmodulin and titin-interacting RhoGEF (OBSCN, OMIM: 608616)19, acting alpha 2 (ACTN2, OMIM: 102573)20, and cysteine and glycine rich protein 3 (CSRP3, OMIM: 600824)21) has also been associated with HCM. Current genetic studies have identified multiple distinct pathogenic variants in the sarcomeric protein gene in approximately 40%-60% of HCM patients, and genetic testing in HCM patients revealed that most pathogenic variants occur in the myosin heavy chain (MYH7) and myosin-binding protein C (MYBPC3). However,the genetic basis for HCM remains elusive. Exploring the pathogenicity of these variations that underlie the human HCM patients remains a major challenge22.
In this study, we report a pathogenic variant in MYH7 in a Chinese Han family with HCM by WES. In order to verify the pathogenicity of this variant, we established a C57BL/6N-Myh7em1(G823E) knockin mice using the CRISPR/Cas9 system. We also discuss plausible mechanisms of this variant.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.5&#215;TBE</td>
			<td>Shanghai Sangon</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>2&#215; Taq Master Mix (Dye Plus)</td>
			<td>Nanjing Novizan Biotechnology Co., Ltd.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Agarose</td>
			<td>Regu</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Anesthesia machine for small animals</td>
			<td>Reward Life Technology Co., Ltd.</td>
			<td>R500</td>
			<td></td>
		</tr>
		<tr>
			<td>BEDTools</td>
			<td></td>
			<td>2.16.1</td>
			<td></td>
		</tr>
		<tr>
			<td>Cas9 in vitro digestion method to detect gRNA target efficiency kit</td>
			<td>Viewsolid Biotechnology Co., Ltd.</td>
			<td>VK007</td>
			<td></td>
		</tr>
		<tr>
			<td>DNA Marker</td>
			<td>Thermo Fisher Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>DNA stabilizer</td>
			<td>Shanghai Seebio Biotechnology Co., Ltd.</td>
			<td>DNAstable LD</td>
			<td>prevent DNA degradation</td>
		</tr>
		<tr>
			<td>Electric paraffin microtome</td>
			<td>Shenyang Hengsong Technology Co., Ltd.</td>
			<td>HS-S7220-B</td>
			<td></td>
		</tr>
		<tr>
			<td>GATK</td>
			<td></td>
			<td>v3.5</td>
			<td></td>
		</tr>
		<tr>
			<td>Gentra Puregene blood kit</td>
			<td>Santa Clara</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Glass slide, coverslip</td>
			<td>Jiangsu Invotech Biotechnology Co., Ltd.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Hematoxylin staining solution, Eosin staining solution</td>
			<td>Shanghai Biyuntian Biotechnology Co., Ltd.</td>
			<td>C0107-500ml, C0109</td>
			<td></td>
		</tr>
		<tr>
			<td>HiSeq X-ten platform</td>
			<td>Illumina</td>
			<td></td>
			<td>perform sequencing on the captured libraries</td>
		</tr>
		<tr>
			<td>Injection of chorionic gonadotropin</td>
			<td>Livzon Pharmaceutical Group Inc.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Injection of pregnant mare serum gonadotropin</td>
			<td>Livzon Pharmaceutical Group Inc.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Isoflurane</td>
			<td>Local suppliers</td>
			<td></td>
			<td>inhalation anesthesia</td>
		</tr>
		<tr>
			<td>Microinjection microscope</td>
			<td>Nikon</td>
			<td>ECLIPSE Ts2</td>
			<td></td>
		</tr>
		<tr>
			<td>NanoDrop</td>
			<td>Thermo Fisher Scientific</td>
			<td>2000</td>
			<td></td>
		</tr>
		<tr>
			<td>Paraffin Embedding Machine</td>
			<td>Shenyang Hengsong Technology Co., Ltd.</td>
			<td>HS-B7126-B</td>
			<td></td>
		</tr>
		<tr>
			<td>Picard</td>
			<td></td>
			<td>(2.2.4) 20</td>
			<td></td>
		</tr>
		<tr>
			<td>Proteinase K</td>
			<td>Merck KGaA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>samtools</td>
			<td></td>
			<td>1.3</td>
			<td></td>
		</tr>
		<tr>
			<td>Sequencer</td>
			<td>Applied Biosystems</td>
			<td>ABI 3500</td>
			<td></td>
		</tr>
		<tr>
			<td>Stereomicroscope</td>
			<td>Nikon</td>
			<td>SMZ745T</td>
			<td></td>
		</tr>
		<tr>
			<td>SureSelect Human All Exon V6</td>
			<td>Agilent Technology Co., Ltd.</td>
			<td></td>
			<td>exome probe</td>
		</tr>
		<tr>
			<td>T7 ARCA mRNA Kit</td>
			<td>New England BioLabs, Inc.</td>
			<td>NEB-E2065S</td>
			<td></td>
		</tr>
		<tr>
			<td>Temperature box</td>
			<td>BINDER GmbH</td>
			<td>KBF-S Solid.Line</td>
			<td></td>
		</tr>
		<tr>
			<td>Trizma Hydrochloride Solution</td>
			<td>Sigma, Merck KGaA</td>
			<td>No. T2663</td>
			<td></td>
		</tr>
		<tr>
			<td>Veterinary ultrasound system</td>
			<td>Royal Philips</td>
			<td>CX50</td>
			<td></td>
		</tr>
	</tbody>
</table>

investigating the pathogenesis of myh7 mutation gly823glu in familial hypertrophic cardiomyopathy using a mouse model

Familial hypertrophic cardiomyopathy (HCM, OMIM: 613690) is the most common cardiomyopathy in China. However, the underlying genetic etiology of HCM remains elusive.
We previously identified a myosin heavy chain 7 (MYH7) gene heterozygous variant, NM_000257.4: c.G2468A (p.G823E), in a large Chinese Han family with HCM. In this family, variant G823E cosegregates with an autosomal dominant disorder. This variant is located in the lever arm domain of the neck region of the MYH7 protein and is highly conserved among homologous myosins and species. To verify the pathogenicity of the G823E variant, we produced a C57BL/6N mouse model with a point mutation (G823E) at the mouse MYH7 locus with CRISPR/Cas9-mediated genome engineering. We designed gRNA targeting vectors and donor oligonucleotides (with targeting sequences flanked by 134 bp of homology). The p.G823E (GGG to GAG) site in the donor oligonucleotide was introduced into exon 23 of MYH7 by homology-directed repair. A silenced p.R819 (AGG to CGA) was also inserted to prevent gRNA binding and re-cleavage of the sequence after homology-directed repair. Echocardiography revealed left ventricular posterior wall (LVPW) hypertrophy with systole in MYH7 G823E/- mice at 2 months of age. These results were likewise validated by histological analysis (Figure 3).
These results demonstrate that the G823E variant plays an important role in the pathogenesis of HCM. Our findings enrich the spectrum of MYH7 variants linked to familial HCM and may provide guidance for genetic counseling and prenatal diagnosis in this Chinese family.

Clinical profile of the families 
The family pedigrees of HCM were obtained and are shown in Figure 2. All the documented family members were diagnosed with HCM at enrollment.
In the family (Figure 2A), the proband was patient III-7, who was diagnosed with HCM and left ventricular outflow tract obstruction (LVOTO) at 46 years old and underwent cardiac surgery. Patient III-3 had minor HCM that did not require surgical treatment. P...

Watch this Scientific Journal Video about Investigating the Pathogenesis of MYH7 Mutation Gly823Glu in Familial Hypertrophic Cardiomyopathy using a Mouse Model at JoVE.com

Investigating the Pathogenesis of MYH7 Mutation Gly823Glu in Familial Hypertrophic Cardiomyopathy using a Mouse Model

Based on the familial hereditary cardiomyopathy family found in our clinical work, we created a C57BL/6N mouse model with a point mutation (G823E) at the mouse MYH7 locus through CRISPR/Cas9-mediated genome engineering to verify this mutation.

Familial hypertrophic cardiomyopathy (HCM, OMIM: 613690) is the most common cardiomyopathy in China. However, the underlying genetic etiology of HCM ...

This protocol is significant as it can provide a demonstration of ultrasound in small animals. This technique may provide insights into the discovery of pathogenic genes in hereditary cardiomyopathy. Fix the knockin mice horizontally on the platform then tilt the platform 30 degrees coddle to the knockin mouse.Remove hair on the anterior chest wall of the knockin mice using a depilatory cream position the probe vertically with the bump facing the animal's head. Then rotate the probe counterclockwise approximately 45 degrees in the para sternal long axis view. Rotate the probe 90 degrees clockwise to obtain the para sternal short axis view.After rotating the probe, adjust the Y axis displacement to get the correct slice. Observe the long axis image of the heart and then select M mode measurement data. Acquire ultrasound data from para sternal long axis views of mice and measure the heart rate, left ventricular ejection fraction, cardiac output, left ventricular and diastolic dimension, left ventricular and systolic dimension.Left ventricular posterior wall and ventricular septum. The family pedigrees of hypertrophic cardiomyopathy were obtained, and all the documented family members were diagnosed with hypertrophic cardiomyopathy enrollment. Sanger sequencing confirmed the same M Y H 7 P G 8 23 E variant in all patients, but not in the healthy individuals in the families.And 174 controls, the heterozygous M Y H 7 P G 8 23 E completely co segregated in this family. The glycine residue at Codon 8 23 in the neck domain region of M Y H 7 was highly conserved in all the available vertebrate myocin sequences. According to A C M G standards and guidelines the M Y H 7 P G 8 23 E variant was predicted to be a pathogenic variant.The knockin mice developed age-dependent cardiac hypertrophy after birth. Echocardiography revealed that the inter ventricular septum and left ventricular posterior wall developed with increased heart rate in the knockin mice. Also confirmed by the histological analysis.Virus ultrasound data can be obtained by rotating the probe at different angles on different sections of the mouse term.

investigating-pathogenesis-myh7-mutation-gly823glu-familial

Research

JoVE Journal

Genetics

2.8K Görüntüleme.  the Second Affiliated Hospital of Guangzhou University of Chinese Medicine. Bu protokol, küçük hayvanlarda ultrasonun gösterilmesini sağlayabildiği için önemlidir. Bu teknik, kalıtsal kardiyomiyopatide patojenik genlerin keşfi hakkında fikir verebilir. Knockin farelerini platforma yatay olarak sabitleyin, ardından platformu knockin faresine 30 derece eğin.Knockin farelerinin ön göğüs duvarındaki kılları, tüy dökücü bir krem pozisyonu kullanarak, probu hayvanın kafasına bakan yumru ile dikey olarak çıkarın. Daha sonra probu saat yö...