rs144420313

Variant names:

• chr14-23419231-G-A
• rs144420313
• NM_000257.4:c.3918C>T

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BA1

This summary comes from the ClinGen Evidence Repository: The filtering allele frequency of the c.3918C>T (p.Leu1306=) variant in the MYH7 gene is 0.55% (60/8654) of East Asian chromosomes by the Exome Aggregation Consortium (http://exac.broadinstitute.org), which is a high enough frequency to be classified as benign based on thresholds defined by the ClinGen Inherited Cardiomyopathy Expert Panel (BA1; PMID:29300372). LINK:https://erepo.genome.network/evrepo/ui/classification/CA014235/MONDO:0004994/002

• Frequency:
  • Genomes: 𝑓 0.00035 (1 hom., cov: 32)
  • Exomes 𝑓: 0.00012 (4 hom.)
• Consequence: MYH7 NM_000257.4 synonymous
• Clinical Significance: Benign reviewed by expert panel B:18
• Conservation: PhyloP100: -1.34

Genes affected

MYH7 (HGNC:7577): (myosin heavy chain 7) Muscle myosin is a hexameric protein containing 2 heavy chain subunits, 2 alkali light chain subunits, and 2 regulatory light chain subunits. This gene encodes the beta (or slow) heavy chain subunit of cardiac myosin. It is expressed predominantly in normal human ventricle. It is also expressed in skeletal muscle tissues rich in slow-twitch type I muscle fibers. Changes in the relative abundance of this protein and the alpha (or fast) heavy subunit of cardiac myosin correlate with the contractile velocity of cardiac muscle. Its expression is also altered during thyroid hormone depletion and hemodynamic overloading. Mutations in this gene are associated with familial hypertrophic cardiomyopathy, myosin storage myopathy, dilated cardiomyopathy, and Laing distal myopathy. [provided by RefSeq, May 2022]

ACMG classification

Verdict is Benign. Variant got -8 ACMG points.

• BA1: For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYH7	NM_000257.4	c.3918C>T	p.Leu1306Leu	synonymous_variant	Exon 29 of 40	ENST00000355349.4	NP_000248.2
MYH7	NM_001407004.1	c.3918C>T	p.Leu1306Leu	synonymous_variant	Exon 28 of 39		NP_001393933.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH7	ENST00000355349.4	c.3918C>T	p.Leu1306Leu	synonymous_variant	Exon 29 of 40	1	NM_000257.4	ENSP00000347507.3

Frequencies

GnomAD3 genomes AF: 0.000348 AC: 53 AN: 152182 Hom.: 1 Cov.: 32

Gnomad AFR AF: 0.000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00731

Gnomad SAS AF: 0.000621

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.000479

GnomAD3 exomes AF: 0.000632 AC: 159 AN: 251464 Hom.: 3 AF XY: 0.000596 AC XY: 81 AN XY: 135914

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00794

Gnomad SAS exome AF: 0.000261

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000489

GnomAD4 exome AF: 0.000118 AC: 172 AN: 1461884 Hom.: 4 Cov.: 33 AF XY: 0.000106 AC XY: 77 AN XY: 727242

Gnomad4 AFR exome AF: 0.000119

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00327

Gnomad4 SAS exome AF: 0.000151

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000360

Gnomad4 OTH exome AF: 0.000331

GnomAD4 genome AF: 0.000348 AC: 53 AN: 152300 Hom.: 1 Cov.: 32 AF XY: 0.000416 AC XY: 31 AN XY: 74466

Gnomad4 AFR AF: 0.000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00733

Gnomad4 SAS AF: 0.000621

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.000474

Alfa AF: 0.0000693 Hom.: 0

Bravo AF: 0.000257

Asia WGS AF: 0.00404 AC: 14 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:18

Revision: reviewed by expert panel

Submissions by phenotype

not specified Benign:6

-

PreventionGenetics, part of Exact Sciences

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jul 01, 2010

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Oct 29, 2013

GeneDx

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

-

Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

-

Clinical Genetics, Academic Medical Center

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Dec 06, 2024

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Cardiomyopathy Benign:3

Dec 15, 2016

ClinGen Cardiomyopathy Variant Curation Expert Panel

Significance: Benign

Review Status: reviewed by expert panel

Collection Method: curation

The filtering allele frequency of the c.3918C>T (p.Leu1306=) variant in the MYH7 gene is 0.55% (60/8654) of East Asian chromosomes by the Exome Aggregation Consortium (http://exac.broadinstitute.org), which is a high enough frequency to be classified as benign based on thresholds defined by the ClinGen Inherited Cardiomyopathy Expert Panel (BA1; PMID:29300372). -

Jan 11, 2024

All of Us Research Program, National Institutes of Health

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Aug 05, 2018

Color Diagnostics, LLC DBA Color Health

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Benign:2

-

Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

-

Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Myosin storage myopathy Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

MYH7-related skeletal myopathy Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Dilated Cardiomyopathy, Dominant Benign:1

Jun 14, 2016

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Left ventricular noncompaction cardiomyopathy Benign:1

Jun 14, 2016

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hypertrophic cardiomyopathy Benign:1

Jan 29, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Cardiovascular phenotype Benign:1

Feb 28, 2024

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Hypertrophic cardiomyopathy 1 Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.39
CADD	Benign	7.5
DANN	Benign	0.82

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs144420313; hg19: chr14-23888440;