rs371855540

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PP2PP3

The NM_000257.4(MYH7):​c.5459G>A​(p.Arg1820Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000186 in 1,613,876 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

MYH7
NM_000257.4 missense

Scores

8
8
4

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:7

Conservation

PhyloP100: 5.63
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 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 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, 0.778

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYH7NM_000257.4 linkc.5459G>A p.Arg1820Gln missense_variant Exon 37 of 40 ENST00000355349.4 NP_000248.2 P12883
MYH7NM_001407004.1 linkc.5459G>A p.Arg1820Gln missense_variant Exon 36 of 39 NP_001393933.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYH7ENST00000355349.4 linkc.5459G>A p.Arg1820Gln missense_variant Exon 37 of 40 1 NM_000257.4 ENSP00000347507.3 P12883
ENSG00000258444ENST00000557368.1 linkn.-244C>T upstream_gene_variant 3

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152248
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000199
AC:
5
AN:
251346
Hom.:
0
AF XY:
0.0000147
AC XY:
2
AN XY:
135868
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000352
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000164
AC:
24
AN:
1461628
Hom.:
0
Cov.:
34
AF XY:
0.0000138
AC XY:
10
AN XY:
727148
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000224
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:
0.0000198
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152248
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74376
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000735
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000567
Hom.:
0
Bravo
AF:
0.0000340
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:7
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Cardiomyopathy Uncertain:3
Jul 20, 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 arginine with glutamine at codon 1820 of the MYH7 protein. Computational prediction tools indicate that this variant has a deleterious impact on protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with distal myopathy and hypertrophic cardiomyopathy (PMID: 27282841), and in an individual affected with arrhythmogenic right ventricular cardiomyopathy (PMID: 30177324). This variant has been identified in 5/251346 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. -

Jul 11, 2024
Color Diagnostics, LLC DBA Color Health
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This missense variant replaces arginine with glutamine at codon 1820 of the MYH7 protein. Computational prediction tools indicate that this variant has a deleterious impact on protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with distal myopathy and hypertrophic cardiomyopathy (PMID: 27282841), and in an individual affected with arrhythmogenic right ventricular cardiomyopathy (PMID: 30177324). This variant has been identified in 5/251346 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 28, 2023
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 Pathogenic:1
Oct 18, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 1820 of the MYH7 protein (p.Arg1820Gln). This variant is present in population databases (rs371855540, gnomAD 0.006%). This missense change has been observed in individual(s) with autosomal recessive MYH7-related conditions (PMID: 27282841). This variant has been reported in individual(s) with autosomal dominant hypertrophic cardiomyopathy (PMID: 37652022; internal data); however, the role of the variant in this condition is currently unclear. ClinVar contains an entry for this variant (Variation ID: 419278). 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%. This variant disrupts the p.Arg1820 amino acid residue in MYH7. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 25666907). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

not specified Uncertain:1
Jul 26, 2019
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant classified as Uncertain Significance - Favor Pathogenic. The p.Arg1820Gln variant in MYH7 has been reported in 1 individual with both hypertrophic cardiomyopathy and distal myopathy as well as in one sibling with only myopathy; however, both individuals as well as a third affected sibling had an additional pathogenic variant sufficient to cause distal myopathy, but which has not been previously associated with cardiomyopathy (Brand 2016). It has also been identified in 1 individual with HCM (LMM data) and has been identified in 5/251346 chromosomes by gnomAD (https://gnomad.broadinstitute.org). It has also been reported in ClinVar (Variation ID #419278). Computational prediction tools and conservation analysis suggest that the p.Arg1820Gln variant may impact the protein, though this information is not predictive enough to determine pathogenicity. In summary, while there is some suspicion for a pathogenic role, the clinical significance of this variant is uncertain. ACMG/AMP Criteria Applied: PM2, PS4_Supporting, PP3. -

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
Sep 22, 2021
Fulgent Genetics, Fulgent Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Uncertain:1
Sep 12, 2018
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The R1820Q variant of uncertain significance in the MYH7 gene has been previously reported in two sisters with distal myopathy, one of whom developed supraventricular tachycardia and HCM at the age of 64 years, however, it was absent from a third sibling with isolated distal myopathy (Brand et al., 2016). Brand et al. (2016) reported that all three siblings in this family also harbored a pathogenic missense variant in the TIA1 gene, which is associated with Welander distal myopathy, and this family had a paternal family history of cardiac disease but further segregation studies of the R1820Q variant were not reported. The R1820Q variant is not observed at a significant frequency in large population cohorts (Lek et al., 2016; 1000 Genomes Consortium et al., 2015; Exome Variant Server). Furthermore, R1820Q is a semi-conservative amino acid substitution, which may impact secondary protein structure as these residues differ in some properties, and this substitution occurs at a position that is conserved across species. Nevertheless, in silico analysis is inconsistent in its predictions as to whether or not the variant is damaging to the protein structure/function. Additionally, although a missense variant at the same residue in the MYH7 gene (R1820W) has been reported in the Human Gene Mutation Database in association with myopathy (Stenson et al., 2014), the clinical significance of this variant also remains to be definitively determined. -

Cardiovascular phenotype Uncertain:1
Mar 11, 2024
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.R1820Q variant (also known as c.5459G>A), located in coding exon 35 of the MYH7 gene, results from a G to A substitution at nucleotide position 5459. The arginine at codon 1820 is replaced by glutamine, an amino acid with highly similar properties. This alteration was detected in two of three siblings in a family, all of whom also carried the TIA1 p.E384K alteration. Phenotypes of the two siblings with both alterations included progressive asymmetric distal limb weakness, mild distal myopathy, supraventricular tachycardia and hypertrophic cardiomyopathy. The third sibling who only carried the TIA1 alteration had isolated distal myopathy (Brand P et al. Neuromuscul. Disord., 2016 08;26:511-5). This variant has also been reported in an individual with arrhythmogenic right ventricular cardiomyopathy (ARVC) and co-occurring DSG2 variants, as well as in an exome cohort with limited clinical details (Homburger JR et al. Proc Natl Acad Sci U S A, 2016 06;113:6701-6; Lin Y et al. J Electrocardiol Jun;51:837-843). This alteration also been reported in association with transposition of the great arteries (Blue GM et al. Am Heart J, 2022 Feb;244:1-13). This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. 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
Benign
0.16
CardioboostCm
Uncertain
0.49
BayesDel_addAF
Uncertain
0.059
T
BayesDel_noAF
Uncertain
0.020
CADD
Pathogenic
31
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.82
D
Eigen
Pathogenic
0.75
Eigen_PC
Pathogenic
0.71
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Uncertain
0.88
D
M_CAP
Pathogenic
0.88
D
MetaRNN
Pathogenic
0.78
D
MetaSVM
Uncertain
0.53
D
MutationAssessor
Pathogenic
3.4
M
PrimateAI
Uncertain
0.69
T
PROVEAN
Benign
-2.3
N
REVEL
Pathogenic
0.66
Sift
Uncertain
0.0010
D
Sift4G
Benign
0.14
T
Polyphen
0.96
P
Vest4
0.47
MVP
0.93
MPC
1.4
ClinPred
0.77
D
GERP RS
5.3
Varity_R
0.61
gMVP
0.85

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs371855540; hg19: chr14-23884304; COSMIC: COSV62515901; COSMIC: COSV62515901; API