14-23433722-G-C

Variant names:

• chr14-23433722-G-C
• rs758659692
• NM_000257.4:c.11C>G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP2 PP3

The NM_000257.4(MYH7):​c.11C>G​(p.Ser4Trp) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,622 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. S4L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MYH7 NM_000257.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.92
• Publications: 10 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: Uncertain_significance. The variant received 4 ACMG points.

• 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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.762

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000257.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYH7	NM_000257.4	MANE Select	c.11C>G	p.Ser4Trp	missense	Exon 3 of 40	NP_000248.2
	MYH7	NM_001407004.1		c.11C>G	p.Ser4Trp	missense	Exon 2 of 39	NP_001393933.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYH7	ENST00000355349.4	TSL:1 MANE Select	c.11C>G	p.Ser4Trp	missense	Exon 3 of 40	ENSP00000347507.3
	MYH7	ENST00000713768.1		c.11C>G	p.Ser4Trp	missense	Exon 3 of 41	ENSP00000519070.1
	MYH7	ENST00000713769.1		c.11C>G	p.Ser4Trp	missense	Exon 2 of 39	ENSP00000519071.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461622 Hom.: 0 Cov.: 35 AF XY: 0.00 AC XY: 0 AN XY: 727120

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86240

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53396

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5586

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111994

Other (OTH) AF: 0.00 AC: 0 AN: 60376

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hypertrophic cardiomyopathy Uncertain:1

Feb 15, 2018

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. A computational algorithm designed to assess the pathogenicity of variants in MYH7 with regard to hypertrophic cardiomyopathy predicted this sequence change to be tolerated. The algorithm has a sensitivity of 94% and a specificity of 89% (PMID: 21310275). This variant has not been reported in the literature in individuals with MYH7-related disease. However, a different sequence change affecting the same codon, p.Ser4Leu, has been reported in individuals affected with hypertrophic cardiomyopathy (PMID: 19150014, 22765922, 25342278). This variant is not present in population databases (ExAC no frequency). This sequence change replaces serine with tryptophan at codon 4 of the MYH7 protein (p.Ser4Trp). The serine residue is weakly conserved and there is a large physicochemical difference between serine and tryptophan.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.42
CardioboostCm	Benign	0.018
BayesDel_addAF	Uncertain	0.067	T
BayesDel_noAF	Benign	-0.14
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Benign	0.39	T
Eigen	Benign	-0.052
Eigen_PC	Benign	-0.045
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Pathogenic	0.77	D
MetaRNN	Pathogenic	0.76	D
MetaSVM	Uncertain	0.058	D
MutationAssessor	Benign	0.84	L
PhyloP100		5.9
PrimateAI	Uncertain	0.49	T
PROVEAN	Benign	-2.3	N
REVEL	Uncertain	0.43
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.060	T
Polyphen		0.92	P
Vest4		0.35
MutPred		0.46		Loss of disorder (P = 0)
MVP		0.94
MPC		2.0
ClinPred		0.80	D
GERP RS		4.1
Varity_R		0.53
gMVP		0.60
Mutation Taster		=20/80	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs758659692; hg19: chr14-23902931;