14-23424923-C-T

Variant names:

• chr14-23424923-C-T
• rs397516154
• NM_000257.4:c.2525G>A

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PS4_Supporting PP1 PM1 PM2_Supporting

This summary comes from the ClinGen Evidence Repository: The c.2525G>A (p.Ser842Asn) variant in MYH7 has been reported in 4 individuals with HCM (PS4_Supporting; Alfares 2015 PMID:25611685; Walsh 2017 PMID:27532257; CHEO pers. comm.; GeneDx pers. comm.; LMM pers. comm.) and segregated with HCM in 3 affected relatives from 1 family (PP1; GeneDx pers. comm.). This variant was absent from large population studies (PM2_Supporting; http://gnomad.broadinstitute.org, v2.1.1). Following the ClinGen Sequence Variant Interpretation (SVI) working group recommendation for weight adjustment of the PM2 criterion due to concerns that rarity in the general population may not meet the relative odds of pathogenicity for moderate evidence, the PM2 criterion was downgraded to PM2_Supporting. This variant lies in the head region of the protein (aa 181-937) and missense variants in this region are statistically more likely to be associated with HCM (PM1; Walsh 2017 PMID:27532257). Computational prediction tools and conservation analysis do not provide strong support for or against an impact to the protein. In summary, due to insufficient evidence, this variant meets criteria to be classified as uncertain significance for hypertrophic cardiomyopathy in an autosomal dominant manner. ACMG/AMP Criteria applied: PS4_Supporting; PP1; PM2_Supporting; PM1. LINK:https://erepo.genome.network/evrepo/ui/classification/CA012535/MONDO:0005045/002

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: MYH7 NM_000257.4 missense
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:3 U:2
• Conservation: PhyloP100: 2.05
• 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: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• hypertrophic cardiomyopathy

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

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

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet
• 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 5 ACMG points.

• PS4: For more information check the summary or visit ClinGen Evidence Repository.
• PM1: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PP1: For more information check the summary or visit ClinGen Evidence Repository.

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYH7	NM_000257.4	MANE Select	c.2525G>A	p.Ser842Asn	missense	Exon 22 of 40	NP_000248.2	P12883
	MYH7	NM_001407004.1		c.2525G>A	p.Ser842Asn	missense	Exon 21 of 39	NP_001393933.1	P12883

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYH7	ENST00000355349.4	TSL:1 MANE Select	c.2525G>A	p.Ser842Asn	missense	Exon 22 of 40	ENSP00000347507.3	P12883
	MYH7	ENST00000858540.1		c.2525G>A	p.Ser842Asn	missense	Exon 22 of 40	ENSP00000528599.1
	MYH7	ENST00000965955.1		c.2525G>A	p.Ser842Asn	missense	Exon 22 of 40	ENSP00000636014.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 6.84e-7 AC: 1 AN: 1461890 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727244

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

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: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112012

Other (OTH) AF: 0.0000166 AC: 1 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
1	-	-	Cardiomyopathy (1)
-	1	-	Familial cardiomyopathy (1)
1	-	-	Hypertrophic cardiomyopathy (1)
1	-	-	not provided (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.52
CardioboostCm	Pathogenic	0.99
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	-0.020
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.48	T
Eigen	Uncertain	0.44
Eigen_PC	Uncertain	0.40
FATHMM_MKL	Uncertain	0.85	D
LIST_S2	Uncertain	0.96	D
M_CAP	Pathogenic	0.92	D
MetaRNN	Pathogenic	0.88	D
MetaSVM	Pathogenic	0.98	D
MutationAssessor	Pathogenic	4.0	H
PhyloP100		2.1
PrimateAI	Pathogenic	0.80	T
PROVEAN	Benign	-2.3	N
REVEL	Uncertain	0.50
Sift	Pathogenic	0.0	D
Sift4G	Benign	0.41	T
Polyphen		0.65	P
Vest4		0.90
MutPred		0.35		Gain of catalytic residue at P838 (P = 0.0044)
MVP		0.97
MPC		2.0
ClinPred		0.98	D
GERP RS		4.7
Varity_R		0.71
gMVP		0.98
Mutation Taster		=11/89	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: rs397516154; hg19: chr14-23894132;