14-23419215-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP2

The NM_000257.4(MYH7):​c.3934C>G​(p.Leu1312Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. 13/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

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

Consequence

MYH7
NM_000257.4 missense

Scores

1
5
14

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: -0.320
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 3 ACMG points.

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.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYH7NM_000257.4 linkc.3934C>G p.Leu1312Val missense_variant Exon 29 of 40 ENST00000355349.4 NP_000248.2 P12883
MYH7NM_001407004.1 linkc.3934C>G p.Leu1312Val missense_variant Exon 28 of 39 NP_001393933.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYH7ENST00000355349.4 linkc.3934C>G p.Leu1312Val missense_variant Exon 29 of 40 1 NM_000257.4 ENSP00000347507.3 P12883

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1461880
Hom.:
0
Cov.:
33
AF XY:
0.00000275
AC XY:
2
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:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
8.99e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Dilated cardiomyopathy 1S;C1842160:Myosin storage myopathy;C1850709:Myopathy, myosin storage, autosomal recessive;C3495498:Hypertrophic cardiomyopathy 1;C4552004:MYH7-related skeletal myopathy Uncertain:1
Mar 08, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Cardiomyopathy Uncertain:1
Mar 06, 2024
Color Diagnostics, LLC DBA Color Health
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This missense variant replaces leucine with valine at codon 1312 of the MYH7 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with cardiovascular disorders in the literature. This variant has not been identified 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. -

Hypertrophic cardiomyopathy Uncertain:1
Aug 17, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

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. 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on MYH7 protein function. ClinVar contains an entry for this variant (Variation ID: 454371). This missense change has been observed in individual(s) with clinical features of MYH7-related disease (Invitae). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces leucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 1312 of the MYH7 protein (p.Leu1312Val). -

Cardiovascular phenotype Uncertain:1
Nov 10, 2020
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.L1312V variant (also known as c.3934C>G), located in coding exon 27 of the MYH7 gene, results from a C to G substitution at nucleotide position 3934. The leucine at codon 1312 is replaced by valine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated 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
Benign
0.088
CardioboostCm
Benign
0.0095
BayesDel_addAF
Benign
-0.084
T
BayesDel_noAF
Benign
-0.36
CADD
Benign
19
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.48
T
Eigen
Benign
-0.45
Eigen_PC
Benign
-0.35
FATHMM_MKL
Benign
0.29
N
LIST_S2
Benign
0.85
D
M_CAP
Pathogenic
0.73
D
MetaRNN
Uncertain
0.43
T
MetaSVM
Uncertain
-0.25
T
MutationAssessor
Benign
0.62
N
PrimateAI
Uncertain
0.58
T
PROVEAN
Benign
0.040
N
REVEL
Benign
0.23
Sift
Benign
0.15
T
Sift4G
Benign
0.13
T
Polyphen
0.0
B
Vest4
0.11
MutPred
0.59
Gain of MoRF binding (P = 0.0954);
MVP
0.75
MPC
0.60
ClinPred
0.15
T
GERP RS
2.9
Varity_R
0.076
gMVP
0.67

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: rs886050419; hg19: chr14-23888424; API