NM_000257.4:c.1182C>A

Variant names:

• chr14-23429304-G-T
• rs1060501452
• NM_000257.4:c.1182C>A

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM1 PM2 PM5 PP2 PP3_Moderate PP5_Very_Strong

The NM_000257.4(MYH7):​c.1182C>A​(p.Asp394Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D394N) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MYH7 NM_000257.4 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 1.08
• Publications: 4 publications found

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 Gene-Disease associations (from GenCC):

• dilated cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• dilated cardiomyopathy 1S

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• hypertrophic cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• hypertrophic cardiomyopathy 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• MYH7-related skeletal myopathy

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
• myopathy, myosin storage, autosomal recessive

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• myopathy, myosin storage, autosomal dominant

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• congenital myopathy 7A, myosin storage, autosomal dominant

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Ebstein anomaly

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• hyaline body myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• left ventricular noncompaction

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• congenital heart disease

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Pathogenic. The variant received 17 ACMG points.

• PM1: In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 22 uncertain in NM_000257.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr14-23429306-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 42828.
• 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 myopathy, myosin storage, autosomal recessive, MYH7-related skeletal myopathy, congenital myopathy 7A, myosin storage, autosomal dominant, Ebstein anomaly, hyaline body myopathy, left ventricular noncompaction, hypertrophic cardiomyopathy 1, dilated cardiomyopathy 1S, dilated cardiomyopathy, congenital heart disease, familial isolated dilated cardiomyopathy, myopathy, myosin storage, autosomal dominant, arrhythmogenic right ventricular cardiomyopathy, hypertrophic cardiomyopathy.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.927
• PP5: Variant 14-23429304-G-T is Pathogenic according to our data. Variant chr14-23429304-G-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 407200.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYH7	NM_000257.4	c.1182C>A	p.Asp394Glu	missense_variant	Exon 13 of 40	ENST00000355349.4	NP_000248.2
MYH7	NM_001407004.1	c.1182C>A	p.Asp394Glu	missense_variant	Exon 12 of 39		NP_001393933.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH7	ENST00000355349.4	c.1182C>A	p.Asp394Glu	missense_variant	Exon 13 of 40	1	NM_000257.4	ENSP00000347507.3
MYH7	ENST00000713768.1	c.1182C>A	p.Asp394Glu	missense_variant	Exon 13 of 41			ENSP00000519070.1
MYH7	ENST00000713769.1	c.1182C>A	p.Asp394Glu	missense_variant	Exon 12 of 39			ENSP00000519071.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:1

Jun 11, 2018

Blueprint Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hypertrophic cardiomyopathy Pathogenic:1

Oct 31, 2016

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces aspartic acid with glutamic acid at codon 394 of the MYH7 protein (p.Asp394Glu). The aspartic acid residue is highly conserved and there is a small physicochemical difference between aspartic acid and glutamic acid. This variant has been reported in several individuals affected with hypertrophic cardiomyopathy (PMID: 23233322, 27532257, Invitae database). In summary, this variant is absent from the population and reported in several affected individuals. However, without additional functional and/or genetic data, this variant has been classified as Likely Pathogenic. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) . -

Hypertrophic cardiomyopathy 1 Pathogenic:1

Feb 26, 2024

3billion

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The variant is not observed in the gnomAD v2.1.1 dataset. Predicted Consequence/Location: The variant is located in a mutational hot spot and/or well-established functional domain in which established pathogenic variants have been reported (PMID: 29300372). In silico tool predictions suggest damaging effect of the variant on gene or gene product [3Cnet: 0.79 (>=0.6, sensitivity 0.72 and precision 0.9)]. Same nucleotide change resulting in same amino acid change has been previously reported as pathogenic/likely pathogenic with strong evidence (ClinVar ID: VCV000407200 /PMID: 23233322 /3billion dataset). A different missense change at the same codon (p.Asp394Asn) has been reported to be associated with MYH7 related disorder (ClinVar ID: VCV000042828). Therefore, this variant is classified as Pathogenic according to the recommendation of ACMG/AMP guideline. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.28
CardioboostCm	Uncertain	0.81
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.18
CADD	Benign	21
DANN	Uncertain	0.98
DEOGEN2	Pathogenic	0.86	D
Eigen	Benign	-0.49
Eigen_PC	Benign	-0.52
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Benign	0.82	T
M_CAP	Pathogenic	0.96	D
MetaRNN	Pathogenic	0.93	D
MetaSVM	Uncertain	-0.15	T
MutationAssessor	Benign	0.11	N
PhyloP100		1.1
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-2.5	D
REVEL	Uncertain	0.59
Sift	Benign	0.27	T
Sift4G	Benign	0.69	T
Polyphen		1.0	D
Vest4		0.90
MutPred		0.55		Gain of catalytic residue at L399 (P = 0.0026);
MVP		0.87
MPC		1.8
ClinPred		0.73	D
GERP RS		3.1
Varity_R		0.31
gMVP		0.94
Mutation Taster		=1/99	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs1060501452; hg19: chr14-23898513;