14-23387854-G-A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PP3_ModerateBS2

The NM_002471.4(MYH6):​c.4429C>T​(p.Arg1477Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000088 in 1,613,966 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. R1477G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000092 ( 0 hom. )

Consequence

MYH6
NM_002471.4 missense

Scores

12
6

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:12

Conservation

PhyloP100: 1.60

Publications

5 publications found
Variant links:
Genes affected
MYH6 (HGNC:7576): (myosin heavy chain 6) Cardiac muscle myosin is a hexamer consisting of two heavy chain subunits, two light chain subunits, and two regulatory subunits. This gene encodes the alpha heavy chain subunit of cardiac myosin. The gene is located approximately 4kb downstream of the gene encoding the beta heavy chain subunit of cardiac myosin. Mutations in this gene cause familial hypertrophic cardiomyopathy and atrial septal defect 3. [provided by RefSeq, Feb 2017]
MYH6 Gene-Disease associations (from GenCC):
  • hypertrophic cardiomyopathy 14
    Inheritance: AD Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, Laboratory for Molecular Medicine
  • Keppen-Lubinsky syndrome
    Inheritance: AD Classification: MODERATE Submitted by: Illumina
  • familial isolated dilated cardiomyopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • atrial septal defect 3
    Inheritance: AD Classification: LIMITED Submitted by: G2P
  • dilated cardiomyopathy
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen
  • hypertrophic cardiomyopathy
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.922
BS2
High AC in GnomAd4 at 8 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYH6NM_002471.4 linkc.4429C>T p.Arg1477Cys missense_variant Exon 31 of 39 ENST00000405093.9 NP_002462.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYH6ENST00000405093.9 linkc.4429C>T p.Arg1477Cys missense_variant Exon 31 of 39 5 NM_002471.4 ENSP00000386041.3

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152080
Hom.:
0
Cov.:
32
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:
0.000118
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000318
AC:
8
AN:
251218
AF XY:
0.0000368
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.0000617
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000917
AC:
134
AN:
1461886
Hom.:
0
Cov.:
37
AF XY:
0.0000784
AC XY:
57
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
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:
86258
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53412
Middle Eastern (MID)
AF:
0.000520
AC:
3
AN:
5768
European-Non Finnish (NFE)
AF:
0.000112
AC:
125
AN:
1112012
Other (OTH)
AF:
0.0000828
AC:
5
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
Heterozygous variant carriers
0
11
21
32
42
53
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:
0.0000526
AC:
8
AN:
152080
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74278
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41376
American (AMR)
AF:
0.00
AC:
0
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5174
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000118
AC:
8
AN:
68030
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000847
Hom.:
0
Bravo
AF:
0.0000756
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:12
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:8
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

Jul 25, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Observed in individuals with hypertrophic cardiomyopathy or sudden cardiac arrest in published literature (Asatryan et al., 2019; van Lint et al., 2019; Filatova et al., 2021); This variant is associated with the following publications: (PMID: 23861362, 22194935, 30975432, 30847666, 24123366, 34598319)

Clinical Genetics, Academic Medical Center
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

Jun 24, 2013
Biesecker Lab/Clinical Genomics Section, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

Sep 02, 2016
Stanford Center for Inherited Cardiovascular Disease, Stanford University
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:provider interpretation

Genome Diagnostics Laboratory, University Medical Center Utrecht
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

Hypertrophic cardiomyopathy 14 Uncertain:1
Dec 15, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 1477 of the MYH6 protein (p.Arg1477Cys). This variant is present in population databases (rs201989347, gnomAD 0.006%). This missense change has been observed in individual(s) with MYH6-related conditions (PMID: 30847666, 34598319). ClinVar contains an entry for this variant (Variation ID: 191711). 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 MYH6 protein function with a positive predictive value of 80%. 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.

Dilated cardiomyopathy 1EE;C2750467:Hypertrophic cardiomyopathy 14;C3279790:Atrial septal defect 3;C3279791:Sick sinus syndrome 3, susceptibility to;C3495498:Hypertrophic cardiomyopathy 1 Uncertain:1
Nov 15, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Dilated cardiomyopathy 1EE Uncertain:1
Sep 02, 2022
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as VUS-3B. Following criteria are met: 0105 - The mechanism of disease for this gene is not clearly established. (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0112 - The condition associated with this gene has incomplete penetrance (PMID: 22194935). (I) 0115 - Variants in this gene are known to have variable expressivity (PMID: 22194935). (I) 0200 - Variant is predicted to result in a missense amino acid change from arginine to cysteine. (I) 0251 - This variant is heterozygous. (I) 0302 - Variant is present in gnomAD <0.001 for a dominant condition (v3: 8 heterozygotes, 0 homozygotes). (SP) 0309 - Multiple alternative amino acid changes at the same position have been observed in gnomAD (highest allele count in v3: 7 heterozygotes, 0 homozygotes). (I) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0600 - Variant is located in the annotated myosin tail domain (DECIPHER). (I) 0710 - Other missense variants comparable to the one identified in this case have inconclusive previous evidence for pathogenicity. p.(Arg1477His), p.(Arg1477Leu) and p.(Arg1477Gly) have been classified as VUS by diagnostic laboratories in ClinVar. (I) 0809 - Previous evidence of pathogenicity for this variant is inconclusive. It was identified in a male with sudden cardiac arrest and classified as a VUS (PMID: 30975432). This classification is supported by multiple diagnostic laboratories in ClinVar. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign

Cardiovascular phenotype Uncertain:1
Mar 20, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R1477C variant (also known as c.4429C>T), located in coding exon 29 of the MYH6 gene, results from a C to T substitution at nucleotide position 4429. The arginine at codon 1477 is replaced by cysteine, an amino acid with highly dissimilar properties. This variant has been detected in a sudden cardiac arrest case and in cases with hypertrophic cardiomyopathy (HCM) or who underwent genetic testing for HCM (Asatryan B et al. Am J Cardiol, 2019 06;123:2031-2038; van Lint FHM et al. Neth Heart J, 2019 Jun;27:304-309; Filatova EV et al. Mol Genet Genomic Med, 2021 11;9:e1808)). This alteration has also been reported as a secondary cardiac variant in an exome cohort and has been detected in an additional exome cohort not selected for the presence of cardiovascular disease; however, clinical details were limited (Ng D et al. Circ Cardiovasc Genet, 2013 Aug;6:337-46; Rodriguez-Flores JL et al. Hum Mutat, 2014 Jan;35:105-16). 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
Pathogenic
0.66
BayesDel_addAF
Pathogenic
0.17
D
BayesDel_noAF
Pathogenic
0.19
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.85
D;D
Eigen
Pathogenic
0.74
Eigen_PC
Uncertain
0.61
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Uncertain
0.88
D;.
M_CAP
Uncertain
0.11
D
MetaRNN
Pathogenic
0.92
D;D
MetaSVM
Pathogenic
0.87
D
MutationAssessor
Pathogenic
3.3
M;M
PhyloP100
1.6
PrimateAI
Pathogenic
0.89
D
PROVEAN
Pathogenic
-5.9
D;D
REVEL
Pathogenic
0.69
Sift
Uncertain
0.0050
D;D
Sift4G
Uncertain
0.0080
D;D
Vest4
0.91
ClinPred
0.95
D
GERP RS
4.4
Varity_R
0.31
gMVP
0.64
Mutation Taster
=67/33
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.13
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: rs201989347; hg19: chr14-23857063; API