NM_000257.4:c.727C>T

Variant names:

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM5PP2PP3_StrongPP5

The NM_000257.4(MYH7):c.727C>T(p.Arg243Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,614,150 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R243H) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

MYH7
NM_000257.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:14U:1

Conservation

PhyloP100: 3.49

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 8 ACMG points.

PM5

Other missense variant is known to change same aminoacid residue: Variant chr14-23431589-C-T 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, 0.986

PP5

Variant 14-23431590-G-A is Pathogenic according to our data. Variant chr14-23431590-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 43101.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=10, Uncertain_significance=1, Pathogenic=1}. Variant chr14-23431590-G-A is described in Lovd as [Likely_pathogenic]. Variant chr14-23431590-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYH7	NM_000257.4 link	c.727C>T	p.Arg243Cys	missense_variant	Exon 8 of 40	ENST00000355349.4	NP_000248.2	P12883
MYH7	NM_001407004.1 link	c.727C>T	p.Arg243Cys	missense_variant	Exon 7 of 39		NP_001393933.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH7	ENST00000355349.4 link	c.727C>T	p.Arg243Cys	missense_variant	Exon 8 of 40	1	NM_000257.4	ENSP00000347507.3		P12883

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152262

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:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000616

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

727246

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000540

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152262

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74392

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:14Uncertain:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Pathogenic:5

Genome Diagnostics Laboratory, University Medical Center Utrecht

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

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

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Jun 01, 2023

CeGaT Center for Human Genetics Tuebingen

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

MYH7: PM1, PM2, PS4:Moderate, PP3 -

Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Aug 12, 2023

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 20350521, 21799269, 27247418, 27532257, 29121657, 25132132, 32830170, 33705529, 30297972, 35653365, 33487615, 29300372) -

Hypertrophic cardiomyopathy 1

Pathogenic:3

Juno Genomics, Hangzhou Juno Genomics, Inc

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PM2_Supporting+PP3+PS4_Moderate+PM1 -

May 16, 2020

Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Nov 19, 2024

North West Genomic Laboratory Hub, Manchester University NHS Foundation Trust

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PM1_Mod PP3_Supp PS3_Supp PS4_Mod -

Hypertrophic cardiomyopathy

Pathogenic:2Uncertain:1

Nov 19, 2021

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

proposed classification - variant undergoing re-assessment, contact laboratory -

Sep 25, 2024

All of Us Research Program, National Institutes of Health

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces arginine with cysteine at codon 243 of the MYH7 protein. Computational prediction suggests that this variant may have a deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). 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 hypertrophic cardiomyopathy (PMID: 27532257). Experimental functional studies using human induced pluripotent stem cells have shown that this variant causes impaired cardiomyocyte relaxation and increased multinucleation (PMID: 33705529). This variant has been reported in individuals affected with hypertrophic cardiomyopathy (PMID: 21799269, 27247418, 27532257, 30297972, 32815737, 32830170). This variant has been identified in 1/31404 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Based on the available evidence, this variant is classified as Likely Pathogenic. -

Dec 19, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 243 of the MYH7 protein (p.Arg243Cys). This variant is present in population databases (rs397516265, gnomAD 0.007%). This missense change has been observed in individuals with autosomal dominant hypertrophic cardiomyopathy (PMID: 21799269, 27247418, 27532257). ClinVar contains an entry for this variant (Variation ID: 43101). 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%. This variant disrupts the p.Arg243 amino acid residue in MYH7. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 18506004, 20965760, 21551322; internal data). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Cardiomyopathy

Pathogenic:2

Nov 14, 2023

Color Diagnostics, LLC DBA Color Health

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces arginine with cysteine at codon 243 of the MYH7 protein. Computational prediction tools indicate that this variant has a deleterious impact on protein structure and function. 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 hypertrophic cardiomyopathy (PMID: 27532257). Experimental functional studies using human induced pluripotent stem cells have shown that this variant causes impaired cardiomyocyte relaxation and increased multinucleation (PMID: 33705529). This variant has been reported in at least six individuals affected with hypertrophic cardiomyopathy (PMID: 21799269, 27247418, 27532257, 30297972, 32815737, 32830170). This variant has been identified in 1/31404 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Based on the available evidence, this variant is classified as Likely Pathogenic. -

Dec 14, 2020

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

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

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

Pathogenic:1

Jul 01, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Cardiovascular phenotype

Pathogenic:1

Feb 23, 2024

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R243C variant (also known as c.727C>T), located in coding exon 6 of the MYH7 gene, results from a C to T substitution at nucleotide position 727. The arginine at codon 243 is replaced by cysteine, an amino acid with highly dissimilar properties. This variant has been reported in association with hypertrophic cardiomyopathy (HCM) (Hirota T et al. J Cardiol, 2010 Jul;56:59-65; Walsh R et al. Genet Med, 2017 Feb;19:192-203; Viswanathan SK et al. PLoS One, 2017 Nov;12:e0187948; Ho CY et al. Circulation, 2018 Oct;138:1387-1398). 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). Another alteration at the same codon, p.R243H (c.728G>A), has been identified in multiple probands with left ventricular noncompaction cardiomyopathy (LVNC), dilated cardiomyopathy, and HCM and has been reported to segregate with disease (Klaassen S et al. Circulation, 2008 Jun;117:2893-901; Chang B et al. Mol. Genet. Metab., 2011 Feb;102:200-6; van Waning JI et al. J. Am. Coll. Cardiol., 2018 Feb;71:711-722; Invitae pers. comm.; OMGL pers. comm.). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

1.0

CardioboostCm

Pathogenic

1.0

BayesDel_addAF

Pathogenic

0.53

BayesDel_noAF

Pathogenic

0.52

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.95

Eigen

Pathogenic

0.71

Eigen_PC

Uncertain

0.53

FATHMM_MKL

Uncertain

0.90

LIST_S2

Pathogenic

0.98

M_CAP

Pathogenic

0.99

MetaRNN

Pathogenic

0.99

MetaSVM

Pathogenic

1.0

MutationAssessor

Pathogenic

4.2

PrimateAI

Pathogenic

0.89

PROVEAN

Pathogenic

-6.5

REVEL

Pathogenic

0.95

Sift

Pathogenic

0.0

Sift4G

Uncertain

0.0030

Polyphen

1.0

Vest4

1.0

MutPred

0.85

Gain of catalytic residue at K246 (P = 0.0041);

MVP

0.99

MPC

2.4

ClinPred

0.99

GERP RS

3.5

Varity_R

0.82

gMVP

0.99

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