NM_000257.4:c.4004C>T

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PP2PP3_Moderate

The NM_000257.4(MYH7):​c.4004C>T​(p.Ser1335Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000062 in 1,613,036 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. S1335A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000066 ( 0 hom. )

Consequence

MYH7
NM_000257.4 missense

Scores

10
9
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:8

Conservation

PhyloP100: 9.72

Publications

10 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: Uncertain_significance. The variant received 3 ACMG points.

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, 0.888

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYH7NM_000257.4 linkc.4004C>T p.Ser1335Leu missense_variant Exon 30 of 40 ENST00000355349.4 NP_000248.2 P12883
MYH7NM_001407004.1 linkc.4004C>T p.Ser1335Leu missense_variant Exon 29 of 39 NP_001393933.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYH7ENST00000355349.4 linkc.4004C>T p.Ser1335Leu missense_variant Exon 30 of 40 1 NM_000257.4 ENSP00000347507.3 P12883
MYH7ENST00000713768.1 linkc.4004C>T p.Ser1335Leu missense_variant Exon 30 of 41 ENSP00000519070.1
MYH7ENST00000713769.1 linkc.4004C>T p.Ser1335Leu missense_variant Exon 29 of 39 ENSP00000519071.1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152220
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.0000400
AC:
10
AN:
249760
AF XY:
0.0000591
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad FIN exome
AF:
0.0000465
Gnomad NFE exome
AF:
0.0000532
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000664
AC:
97
AN:
1460698
Hom.:
0
Cov.:
32
AF XY:
0.0000674
AC XY:
49
AN XY:
726528
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33456
American (AMR)
AF:
0.00
AC:
0
AN:
44688
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26096
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39672
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86206
European-Finnish (FIN)
AF:
0.0000188
AC:
1
AN:
53198
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5694
European-Non Finnish (NFE)
AF:
0.0000837
AC:
93
AN:
1111338
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60350
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
6
12
19
25
31
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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
AF:
0.0000197
AC:
3
AN:
152338
Hom.:
0
Cov.:
33
AF XY:
0.0000268
AC XY:
2
AN XY:
74502
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41580
American (AMR)
AF:
0.00
AC:
0
AN:
15308
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68024
Other (OTH)
AF:
0.000473
AC:
1
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000785
Hom.:
0
Bravo
AF:
0.0000264
TwinsUK
AF:
0.000539
AC:
2
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cardiomyopathy Uncertain:3
Sep 27, 2024
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces serine with leucine at codon 1335 of the MYH7 protein. Computational prediction suggests that this variant may have a deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in individuals affected with dilated cardiomyopathy (PMID: 27532257, 29773157, 31983221). It has also been reported in an individual affected with hypertrophic cardiomyopathy (PMID: 27532257) and in an individual affected with left ventricular noncompaction (PMID: 31918855). This variant has been identified in 10/249760 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Jun 15, 2023
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces serine with leucine at codon 1335 of the MYH7 protein. Computational prediction suggests that this variant may have a deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in individuals affected with dilated cardiomyopathy (PMID: 27532257, 29773157, 31983221). It has also been reported in an individual affected with hypertrophic cardiomyopathy (PMID: 27532257) and in an individual affected with left ventricular noncompaction (PMID: 31918855). This variant has been identified in 10/249760 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Apr 20, 2022
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Apr 04, 2014
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

proposed classification - variant undergoing re-assessment, contact laboratory -

Congenital myopathy with fiber type disproportion;C1834481:Dilated cardiomyopathy 1S;C1842160:Myosin storage myopathy;C1850709:Myopathy, myosin storage, autosomal recessive;C3495498:Hypertrophic cardiomyopathy 1;C4552004:MYH7-related skeletal myopathy Uncertain:1
Aug 09, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Dec 18, 2018
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

A variant of uncertain significance has been identified in the MYH7 gene. The S1335L variant has reported as a variant of unknown pathogenicity, identified in 1/3200 cardiomyopathy patients (Walsh et al., 2017), though no clinical details or segregation data were provided. The S1335L variant is not observed at a significant frequency in large population cohorts (Lek et al., 2016). However, this variant has been identified in one other individual referred for HCM testing at GeneDx. Thus far, segregation data is absent for this individual due to lack of participation by informative family members. This variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is conserved across species and in silico analysis predicts this variant is probably damaging to the protein structure/function. Thus, this variant lacks observation in a significant number of affected individuals, segregation data, and functional evidence, which would further clarify its pathogenicity. Therefore, based on the currently available information, it is unclear whether this variant is pathogenic or rare benign. -

Hypertrophic cardiomyopathy Uncertain:1
Jun 06, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces serine, which is neutral and polar, with leucine, which is neutral and non-polar, at codon 1335 of the MYH7 protein (p.Ser1335Leu). This variant is present in population databases (rs397516199, gnomAD 0.006%). This missense change has been observed in individual(s) with hypertrophic cardiomyopathy or dilated cardiomyopathy (PMID: 27532257, 31918855, 37652022; Invitae). ClinVar contains an entry for this variant (Variation ID: 42987). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae 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. -

Cardiovascular phenotype Uncertain:1
Mar 25, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.S1335L variant (also known as c.4004C>T), located in coding exon 28 of the MYH7 gene, results from a C to T substitution at nucleotide position 4004. The serine at codon 1335 is replaced by leucine, an amino acid with dissimilar properties. This variant has been detected in dilated and hypertrophic cardiomyopathy cohorts; however, details were limited (Walsh R et al. Genet. Med., 2017 02;19:192-203; Ware JS et al. J. Am. Coll. Cardiol., 2018 05;71:2293-2302). This variant has also been reported in left ventricular non-compaction (LVNC) and biobank cohorts (Park J et al. Hum Mol Genet, 2022 Mar;31:827-837; Liu S et al. Int J Cardiol, 2020 Mar;302:117-123). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.42
CardioboostCm
Uncertain
0.48
BayesDel_addAF
Pathogenic
0.23
D
BayesDel_noAF
Pathogenic
0.26
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.82
D
Eigen
Uncertain
0.41
Eigen_PC
Uncertain
0.50
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.91
D
M_CAP
Pathogenic
0.88
D
MetaRNN
Pathogenic
0.89
D
MetaSVM
Uncertain
0.19
D
MutationAssessor
Pathogenic
3.3
M
PhyloP100
9.7
PrimateAI
Pathogenic
0.86
D
PROVEAN
Uncertain
-3.7
D
REVEL
Pathogenic
0.78
Sift
Pathogenic
0.0
D
Sift4G
Uncertain
0.022
D
Polyphen
0.027
B
Vest4
0.72
MVP
0.97
MPC
1.5
ClinPred
0.93
D
GERP RS
5.0
Varity_R
0.55
gMVP
0.86
Mutation Taster
=18/82
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs397516199; hg19: chr14-23887584; COSMIC: COSV62516785; COSMIC: COSV62516785; API