14-23424940-G-C

Variant names:

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2PM5PP2PP3_Moderate

The NM_000257.4(MYH7):c.2508C>G(p.Ile836Met) variant causes a missense change. The variant allele was found at a frequency of 0.00000186 in 1,614,074 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I836T) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

MYH7
NM_000257.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7

Conservation

PhyloP100: 4.62

Variant links:

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]

MYH7 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr14-23424941-A-G is described in Lovd as [Pathogenic].

PP2

Missense variant in the MYH7 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 341 curated pathogenic missense variants (we use a threshold of 10). The gene has 16 curated benign missense variants. Gene score misZ: 3.9329 (above the threshold of 3.09). Trascript score misZ: 6.7889 (above the threshold of 3.09). GenCC associations: The gene is linked to hyaline body myopathy, MYH7-related skeletal myopathy, dilated cardiomyopathy 1S, congenital myopathy 7A, myosin storage, autosomal dominant, dilated cardiomyopathy, left ventricular noncompaction, myopathy, myosin storage, autosomal dominant, hypertrophic cardiomyopathy, congenital heart disease, Ebstein anomaly, arrhythmogenic right ventricular cardiomyopathy, myopathy, myosin storage, autosomal recessive, hypertrophic cardiomyopathy 1, familial isolated dilated cardiomyopathy.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.914

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYH7	NM_000257.4 link	c.2508C>G	p.Ile836Met	missense_variant	Exon 22 of 40	ENST00000355349.4	NP_000248.2	P12883
MYH7	NM_001407004.1 link	c.2508C>G	p.Ile836Met	missense_variant	Exon 21 of 39		NP_001393933.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH7	ENST00000355349.4 link	c.2508C>G	p.Ile836Met	missense_variant	Exon 22 of 40	1	NM_000257.4	ENSP00000347507.3		P12883

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152190

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000192

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000137

AC:

AN:

1461884

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727242

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

8.99e-7

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152190

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74354

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000192

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Cardiomyopathy

Uncertain:2

Apr 03, 2017

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Oct 29, 2024

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces isoleucine with methionine at codon 836 of the MYH7 protein. This variant is found within a highly conserved region of the myosin head domain. Missense variants in this region have been shown to be significantly overrepresented in individuals with affected with hypertrophic cardiomyopathy (PMID: 27532257). Computational prediction suggests that this variant may have deleterious impact on protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with hypertrophic cardiomyopathy (PMID: 27247418, 30297972) and in an individual affected with dilated cardiomyopathy (PMID: 34137518). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

not specified

Uncertain:1

Dec 12, 2011

Stanford Center for Inherited Cardiovascular Disease, Stanford University

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

Note this variant was found in clinical genetic testing performed by one or more labs who may also submit to ClinVar. Thus any internal case data may overlap with the internal case data of other labs. The interpretation reviewed below is that of the Stanford Center for Inherited Cardiovascular Disease. This variant is novel. This variant is located in coding exon 20. The isoleucine at codon 836 is replaced by methionine, an amino acid with highly similar properties. In silico analysis with PolyPhen-2 predicts the variant to be probably damaging. Mutation taster predicts this variant to be disease-causing. The Isoleucine at codon 836 is conserved across vertebrae species, as are neighboring amino acids. Other variants have been reported in association with disease at nearby codons (Lys835Thr; Pro838Leu). In total the variant has not been seen in ~6,500 laboratory controls and individuals from publicly available population datasets. There is no variation at codon 836 listed in the NHLBI Exome Sequencing Project dataset, which currently includes variant calls on ~6,500 Caucasian and African American individuals (as of 9/13/13). Note that this dataset does not match the patient's ancestry (Phillipines). There is also no variation at this codon listed in dbSNP or 1000 genomes (as of 9/13/13). -

Congenital myopathy with fiber type disproportion;C1834481:Dilated cardiomyopathy 1S;C1842160:Myosin storage myopathy;C1850709:Myopathy, myosin storage, autosomal recessive;C3495498:Hypertrophic cardiomyopathy 1;C4552004:MYH7-related skeletal myopathy

Uncertain:1

Oct 06, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Primary dilated cardiomyopathy

Uncertain:1

Genetics and Genomics Program, Sidra Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: research

- -

Hypertrophic cardiomyopathy

Uncertain:1

Oct 22, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 836 of the MYH7 protein (p.Ile836Met). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with hypertrophic cardiomyopathy (PMID: 27247418). ClinVar contains an entry for this variant (Variation ID: 235030). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt MYH7 protein function with a positive predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Cardiovascular phenotype

Uncertain:1

Aug 28, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.I836M variant (also known as c.2508C>G), located in coding exon 20 of the MYH7 gene, results from a C to G substitution at nucleotide position 2508. The isoleucine at codon 836 is replaced by methionine, an amino acid with highly similar properties. This alteration is located in the myosin head domain, which contains a statistically significant clustering of pathogenic missense variants (Homburger JR et al. Proc Natl Acad Sci U S A, 2016 06;113:6701-6; Walsh R et al. Genet Med, 2017 02;19:192-203; Ambry internal data). This variant was reported in one individual from a hypertrophic cardiomyopathy (HCM) cohort with limited details provided (Homburger JR et al. Proc Natl Acad Sci U S A, 2016 06;113:6701-6). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.23

CardioboostCm

Pathogenic

1.0

BayesDel_addAF

Pathogenic

0.33

BayesDel_noAF

Pathogenic

0.24

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.43

Eigen

Uncertain

0.55

Eigen_PC

Uncertain

0.49

FATHMM_MKL

Uncertain

0.96

LIST_S2

Benign

0.85

M_CAP

Pathogenic

0.82

MetaRNN

Pathogenic

0.91

MetaSVM

Pathogenic

0.86

MutationAssessor

Pathogenic

3.0

PrimateAI

Uncertain

0.74

PROVEAN

Benign

-1.8

REVEL

Pathogenic

0.79

Sift

Benign

0.069

Sift4G

Benign

0.078

Polyphen

1.0

Vest4

0.84

MutPred

0.59

Gain of catalytic residue at Y833 (P = 0.0075);

MVP

0.96

MPC

2.1

ClinPred

0.94

GERP RS

3.7

Varity_R

0.38

gMVP

0.98

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over