14-23427685-C-G

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1PM2PP2PP3_Strong

The NM_000257.4(MYH7):​c.1788G>C​(p.Lys596Asn) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,892 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 nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Synonymous variant affecting the same amino acid position (i.e. K596K) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

MYH7
NM_000257.4 missense

Scores

15
4
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 3.85

Publications

2 publications found
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 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

PM1
In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 13 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.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.941

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYH7NM_000257.4 linkc.1788G>C p.Lys596Asn missense_variant Exon 16 of 40 ENST00000355349.4 NP_000248.2 P12883
MYH7NM_001407004.1 linkc.1788G>C p.Lys596Asn missense_variant Exon 15 of 39 NP_001393933.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYH7ENST00000355349.4 linkc.1788G>C p.Lys596Asn missense_variant Exon 16 of 40 1 NM_000257.4 ENSP00000347507.3 P12883
MYH7ENST00000713768.1 linkc.1788G>C p.Lys596Asn missense_variant Exon 16 of 41 ENSP00000519070.1
MYH7ENST00000713769.1 linkc.1788G>C p.Lys596Asn missense_variant Exon 15 of 39 ENSP00000519071.1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251494
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.0000992
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1461892
Hom.:
0
Cov.:
32
AF XY:
0.00000275
AC XY:
2
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000765
AC:
2
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:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cardiomyopathy Uncertain:1
Apr 13, 2018
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hypertrophic cardiomyopathy Uncertain:1
Nov 01, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces lysine, which is basic and polar, with asparagine, which is neutral and polar, at codon 596 of the MYH7 protein (p.Lys596Asn). This variant is present in population databases (rs606231325, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with MYH7-related conditions. ClinVar contains an entry for this variant (Variation ID: 915604). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt MYH7 protein function with a positive predictive value of 95%. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
CardioboostCm
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.34
D
BayesDel_noAF
Pathogenic
0.26
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.96
D
Eigen
Uncertain
0.50
Eigen_PC
Uncertain
0.32
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Pathogenic
0.99
D
M_CAP
Pathogenic
0.97
D
MetaRNN
Pathogenic
0.94
D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
4.4
H
PhyloP100
3.9
PrimateAI
Uncertain
0.74
T
PROVEAN
Pathogenic
-4.5
D
REVEL
Pathogenic
0.83
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
0.64
P
Vest4
0.96
MutPred
0.64
Loss of methylation at K596 (P = 7e-04);
MVP
0.94
MPC
2.2
ClinPred
0.99
D
GERP RS
3.0
Varity_R
0.93
gMVP
0.93
Mutation Taster
=2/98
disease causing

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

Other links and lift over

dbSNP: rs606231325; hg19: chr14-23896894; COSMIC: COSV62518507; API