14-23415096-G-T

Variant names:

• chr14-23415096-G-T
• rs145734640
• NM_000257.4:c.5458C>A

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Moderate BP6 BP7

The NM_000257.4(MYH7):​c.5458C>A​(p.Arg1820Arg) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000178 in 1,461,560 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. R1820R) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000018 (0 hom.)
• Consequence: MYH7 NM_000257.4 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:2
• Conservation: PhyloP100: 2.66
• Publications: 8 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

ENSG00000258444 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -4 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.42).
• BP6: Variant 14-23415096-G-T is Benign according to our data. Variant chr14-23415096-G-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 837357.
• BP7: Synonymous conserved (PhyloP=2.66 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYH7	NM_000257.4	c.5458C>A	p.Arg1820Arg	synonymous_variant	Exon 37 of 40	ENST00000355349.4	NP_000248.2
MYH7	NM_001407004.1	c.5458C>A	p.Arg1820Arg	synonymous_variant	Exon 36 of 39		NP_001393933.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH7	ENST00000355349.4	c.5458C>A	p.Arg1820Arg	synonymous_variant	Exon 37 of 40	1	NM_000257.4	ENSP00000347507.3
MYH7	ENST00000713768.1	c.5458C>A	p.Arg1820Arg	synonymous_variant	Exon 37 of 41			ENSP00000519070.1
MYH7	ENST00000713769.1	c.5458C>A	p.Arg1820Arg	synonymous_variant	Exon 36 of 39			ENSP00000519071.1
ENSG00000258444	ENST00000557368.1	n.-243G>T		upstream_gene_variant		3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251292 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000178 AC: 26 AN: 1461560 Hom.: 0 Cov.: 34 AF XY: 0.0000165 AC XY: 12 AN XY: 727120

African (AFR) AF: 0.00 AC: 0 AN: 33476

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: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53170

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5712

European-Non Finnish (NFE) AF: 0.0000225 AC: 25 AN: 1112010

Other (OTH) AF: 0.0000166 AC: 1 AN: 60382

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Cardiovascular phenotype Uncertain:1

Oct 01, 2021

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.5458C>A (p.R1820R) alteration is located in exon 37 (coding exon 35) of the MYH7 gene. This alteration consists of a C to A substitution at nucleotide position 5458. This nucleotide substitution does not change the amino acid at codon 1820. However, this change occurs in the last nucleotide of Exon 37 (c.5284_5559) which makes it likely to have some effect on normal mRNA splicing. Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Cardiomyopathy Benign:1

Jul 29, 2024

All of Us Research Program, National Institutes of Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hypertrophic cardiomyopathy Benign:1

Feb 24, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.42
CADD	Benign	15
DANN	Benign	0.89
PhyloP100		2.7
Mutation Taster		=100/0	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.19		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: rs145734640; hg19: chr14-23884305;