14-23432703-C-G

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 13 ACMG points: 13P and 0B. PS1PM2PP2PP3_StrongPP5_Moderate

The NM_000257.4(MYH7):c.438G>C(p.Lys146Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,880 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 Likely pathogenic (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in Lovd.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

MYH7
NM_000257.4 missense

Scores

Clinical Significance

Likely pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 3.30

Variant links:

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 links:

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 13 ACMG points.

PS1

Transcript NM_000257.4 (MYH7) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in Lovd

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 hyaline body myopathy, MYH7-related skeletal myopathy, dilated cardiomyopathy 1S, congenital myopathy 7A, myosin storage, autosomal dominant, dilated cardiomyopathy, left ventricular noncompaction, myopathy, myosin storage, autosomal dominant, hypertrophic cardiomyopathy, congenital heart disease, Ebstein anomaly, arrhythmogenic right ventricular cardiomyopathy, myopathy, myosin storage, autosomal recessive, hypertrophic cardiomyopathy 1, familial isolated dilated cardiomyopathy.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.961

PP5

Variant 14-23432703-C-G is Pathogenic according to our data. Variant chr14-23432703-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 3230910.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 link	c.438G>C	p.Lys146Asn	missense_variant	Exon 5 of 40	ENST00000355349.4	NP_000248.2	P12883
MYH7	NM_001407004.1 link	c.438G>C	p.Lys146Asn	missense_variant	Exon 4 of 39		NP_001393933.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH7	ENST00000355349.4 link	c.438G>C	p.Lys146Asn	missense_variant	Exon 5 of 40	1	NM_000257.4	ENSP00000347507.3		P12883

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461880

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727240

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

8.99e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Cardiovascular phenotype

Pathogenic:1

Nov 10, 2023

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.K146N variant (also known as c.438G>C), located in coding exon 3 of the MYH7 gene, results from a G to C substitution at nucleotide position 438. The lysine at codon 146 is replaced by asparagine, an amino acid with similar properties. This variant (and c.438G>T, which also results in p.K146N) has been detected in probands with hypertrophic cardiomyopathy (HCM), including a de novo occurrence, and has been reported to segregate with HCM in at least one family (Ingles J et al. J Med Genet, 2005 Oct;42:e59; Walsh R et al. Genet Med, 2017 Feb;19:192-203; Ross SB et al. Circ Cardiovasc Genet, 2017 Jun;10; Morita H et al. N Engl J Med, 2008 May;358:1899-908). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.99

CardioboostCm

Pathogenic

0.97

BayesDel_addAF

Uncertain

0.055

BayesDel_noAF

Benign

-0.16

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.85

Eigen

Benign

0.17

Eigen_PC

Benign

0.10

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.86

M_CAP

Pathogenic

0.95

MetaRNN

Pathogenic

0.96

MetaSVM

Uncertain

0.30

MutationAssessor

Benign

0.75

PrimateAI

Pathogenic

0.86

PROVEAN

Uncertain

-3.1

REVEL

Pathogenic

0.75

Sift

Uncertain

0.0010

Sift4G

Uncertain

0.0020

Polyphen

0.99

Vest4

0.86

MutPred

0.77

Gain of catalytic residue at P151 (P = 5e-04);

MVP

0.92

MPC

2.3

ClinPred

0.99

GERP RS

2.7

Varity_R

0.73

gMVP

0.91

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

Publications

No publications associated with this variant yet.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over