14-23432703-C-G

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PS1_Very_StrongPM1PM2PP2PP3_StrongPP5_Moderate

The NM_000257.4(MYH7):​c.438G>C​(p.Lys146Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,880 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 Likely pathogenic (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar. Synonymous variant affecting the same amino acid position (i.e. K146K) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

MYH7
NM_000257.4 missense

Scores

7
8
5

Clinical Significance

Likely pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 3.30

Publications

0 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: Pathogenic. The variant received 19 ACMG points.

PS1
Transcript NM_000257.4 (MYH7) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
PM1
In a hotspot region, there are 10 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 22 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, 0.961
PP5
Variant 14-23432703-C-G is Pathogenic according to our data. Variant chr14-23432703-C-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 3230910.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYH7NM_000257.4 linkc.438G>C p.Lys146Asn missense_variant Exon 5 of 40 ENST00000355349.4 NP_000248.2
MYH7NM_001407004.1 linkc.438G>C p.Lys146Asn missense_variant Exon 4 of 39 NP_001393933.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYH7ENST00000355349.4 linkc.438G>C p.Lys146Asn missense_variant Exon 5 of 40 1 NM_000257.4 ENSP00000347507.3
MYH7ENST00000713768.1 linkc.438G>C p.Lys146Asn missense_variant Exon 5 of 41 ENSP00000519070.1
MYH7ENST00000713769.1 linkc.438G>C p.Lys146Asn missense_variant Exon 4 of 39 ENSP00000519071.1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461880
Hom.:
0
Cov.:
33
AF XY:
0.00000138
AC XY:
1
AN XY:
727240
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1112010
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Cardiovascular phenotype Pathogenic:1
Nov 10, 2023
Ambry Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.K146N variant (also known as c.438G>C), located in coding exon 3 of the MYH7 gene, results from a G to C substitution at nucleotide position 438. The lysine at codon 146 is replaced by asparagine, an amino acid with similar properties. This variant (and c.438G>T, which also results in p.K146N) has been detected in probands with hypertrophic cardiomyopathy (HCM), including a de novo occurrence, and has been reported to segregate with HCM in at least one family (Ingles J et al. J Med Genet, 2005 Oct;42:e59; Walsh R et al. Genet Med, 2017 Feb;19:192-203; Ross SB et al. Circ Cardiovasc Genet, 2017 Jun;10; Morita H et al. N Engl J Med, 2008 May;358:1899-908). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
CardioboostCm
Pathogenic
0.97
BayesDel_addAF
Uncertain
0.055
T
BayesDel_noAF
Benign
-0.16
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.85
D
Eigen
Benign
0.17
Eigen_PC
Benign
0.10
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.86
D
M_CAP
Pathogenic
0.95
D
MetaRNN
Pathogenic
0.96
D
MetaSVM
Uncertain
0.30
D
MutationAssessor
Benign
0.75
N
PhyloP100
3.3
PrimateAI
Pathogenic
0.86
D
PROVEAN
Uncertain
-3.1
D
REVEL
Pathogenic
0.75
Sift
Uncertain
0.0010
D
Sift4G
Uncertain
0.0020
D
Polyphen
0.99
D
Vest4
0.86
MutPred
0.77
Gain of catalytic residue at P151 (P = 5e-04);
MVP
0.92
MPC
2.3
ClinPred
0.99
D
GERP RS
2.7
Varity_R
0.73
gMVP
0.91
Mutation Taster
=18/82
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: rs397516212; hg19: chr14-23901912; API