14-23414101-G-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PM5PP2PP3

The NM_000257.4(MYH7):​c.5561C>A​(p.Thr1854Lys) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. 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. T1854M) has been classified as Pathogenic.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

MYH7
NM_000257.4 missense, splice_region

Scores

11
6
3
Splicing: ADA: 0.9929
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 7.97
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]

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ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr14-23414101-G-A is described in Lovd as [Pathogenic].
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
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYH7NM_000257.4 linkc.5561C>A p.Thr1854Lys missense_variant, splice_region_variant Exon 38 of 40 ENST00000355349.4 NP_000248.2 P12883
MYH7NM_001407004.1 linkc.5561C>A p.Thr1854Lys missense_variant, splice_region_variant Exon 37 of 39 NP_001393933.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYH7ENST00000355349.4 linkc.5561C>A p.Thr1854Lys missense_variant, splice_region_variant Exon 38 of 40 1 NM_000257.4 ENSP00000347507.3 P12883

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
1459770
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
726264
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:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:1
Oct 17, 2024
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The MYH7 c.5561C>A; p.Thr1854Lys variant, to our knowledge, is not reported in the medical literature or gene specific databases. This variant is also absent from the Genome Aggregation Database (v2.1.1), indicating it is not a common polymorphism. Computational analyses predict that this variant is deleterious (REVEL: 0.758). Additionally, computational splicing analyses (SpliceAI) predict that this variant may impact splicing by creating a novel cryptic acceptor splice site, although RNA analysis would be required to confirm this. Given the lack of clinical and functional data, the significance of this variant is uncertain at this time. -

Hypertrophic cardiomyopathy Uncertain:1
Feb 22, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces threonine, which is neutral and polar, with lysine, which is basic and polar, at codon 1854 of the MYH7 protein (p.Thr1854Lys). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with MYH7-related conditions. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. This variant disrupts the p.Thr1854 amino acid residue in MYH7. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 15358028, 23283745, 25086479, 27532257; Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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
Jan 02, 2024
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.T1854K variant (also known as c.5561C>A), located in coding exon 36 of the MYH7 gene, results from a C to A substitution at nucleotide position 5561. The threonine at codon 1854 is replaced by lysine, an amino acid with similar properties. This amino acid position is well 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
Pathogenic
0.65
CardioboostCm
Uncertain
0.71
BayesDel_addAF
Pathogenic
0.37
D
BayesDel_noAF
Pathogenic
0.29
CADD
Pathogenic
37
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.82
D
Eigen
Pathogenic
0.80
Eigen_PC
Pathogenic
0.74
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.88
D
M_CAP
Pathogenic
0.77
D
MetaRNN
Pathogenic
0.92
D
MetaSVM
Uncertain
0.43
D
MutationAssessor
Pathogenic
3.0
M
PrimateAI
Uncertain
0.72
T
PROVEAN
Benign
-2.3
N
REVEL
Pathogenic
0.76
Sift
Uncertain
0.0020
D
Sift4G
Benign
0.26
T
Polyphen
0.97
D
Vest4
0.68
MutPred
0.48
Gain of ubiquitination at T1854 (P = 0.0066);
MVP
0.99
MPC
1.6
ClinPred
0.96
D
GERP RS
5.1
Varity_R
0.56
gMVP
0.98

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
0.99
dbscSNV1_RF
Pathogenic
0.87
SpliceAI score (max)
0.94
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.94
Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr14-23883310; API