rs878853842

Variant names:

• chr14-23431453-G-T
• rs878853842
• NM_000257.4:c.761C>A

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP5_Moderate

The NM_000257.4(MYH7):​c.761C>A​(p.Ala254Glu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: MYH7 NM_000257.4 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.86
• Publications: 3 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: Likely_pathogenic. The variant received 7 ACMG points.

• PM1: In a hotspot region, there are 14 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 18 uncertain in NM_000257.4
• PM2: Very rare variant in population databases, with high coverage
• 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.
• PP5: Variant 14-23431453-G-T is Pathogenic according to our data. Variant chr14-23431453-G-T is described in ClinVar as Pathogenic. ClinVar VariationId is 237444.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYH7	NM_000257.4	c.761C>A	p.Ala254Glu	missense_variant	Exon 9 of 40	ENST00000355349.4	NP_000248.2
MYH7	NM_001407004.1	c.761C>A	p.Ala254Glu	missense_variant	Exon 8 of 39		NP_001393933.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH7	ENST00000355349.4	c.761C>A	p.Ala254Glu	missense_variant	Exon 9 of 40	1	NM_000257.4	ENSP00000347507.3
MYH7	ENST00000713768.1	c.761C>A	p.Ala254Glu	missense_variant	Exon 9 of 41			ENSP00000519070.1
MYH7	ENST00000713769.1	c.761C>A	p.Ala254Glu	missense_variant	Exon 8 of 39			ENSP00000519071.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hypertrophic cardiomyopathy Pathogenic:1

Nov 23, 2016

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is found within a region of MYH7 between codons 181 and 937 that contains the majority of the myosin head domain. Missense variants in this region have been shown to be significantly overrepresented in individuals with hypertrophic cardiomyopathy (PMID: 27532257). Family studies have indicated that this variant was not present in the parents of an individual with hypertrophic cardiomyopathy, which suggests that it was de novo in that affected individual (Invitae). For these reasons, this variant has been classified as Pathogenic. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a MYH7-related disease. This sequence change replaces alanine with glutamic acid at codon 254 of the MYH7 protein (p.Ala254Glu). The alanine residue is highly conserved and there is a moderate physicochemical difference between alanine and glutamic acid. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
CardioboostCm	Uncertain	0.51
BayesDel_addAF	Uncertain	0.076	D
BayesDel_noAF	Benign	-0.13
CADD	Uncertain	24
DANN	Benign	0.92
DEOGEN2	Uncertain	0.72	D
Eigen	Benign	-0.17
Eigen_PC	Benign	-0.094
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.88	D
M_CAP	Pathogenic	0.78	D
MetaRNN	Uncertain	0.54	D
MetaSVM	Uncertain	-0.13	T
MutationAssessor	Benign	0.42	N
PhyloP100		7.9
PrimateAI	Uncertain	0.74	T
PROVEAN	Benign	-1.6	N
REVEL	Uncertain	0.40
Sift	Benign	0.034	D
Sift4G	Benign	0.39	T
Polyphen		0.0030	B
Vest4		0.45
MutPred		0.43		Gain of catalytic residue at R249 (P = 6e-04);
MVP		0.91
MPC		1.6
ClinPred		0.70	D
GERP RS		3.5
Varity_R		0.64
gMVP		0.78
Mutation Taster		=14/86	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: rs878853842; hg19: chr14-23900662;