rs202120238

Variant summary

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

The NM_002471.4(MYH6):​c.2383C>T​(p.Arg795Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00016 in 1,614,090 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. R795Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00014 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00016 ( 0 hom. )

Consequence

MYH6
NM_002471.4 missense

Scores

13
5
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 0.743

Publications

6 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, 0.919
BS2
High AC in GnomAd4 at 21 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYH6NM_002471.4 linkc.2383C>T p.Arg795Trp missense_variant Exon 20 of 39 ENST00000405093.9 NP_002462.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYH6ENST00000405093.9 linkc.2383C>T p.Arg795Trp missense_variant Exon 20 of 39 5 NM_002471.4 ENSP00000386041.3 P13533
ENSG00000289973ENST00000702194.1 linkn.-49C>T upstream_gene_variant

Frequencies

GnomAD3 genomes
AF:
0.000138
AC:
21
AN:
152172
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000483
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000386
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000250
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000995
AC:
25
AN:
251340
AF XY:
0.000110
show subpopulations
Gnomad AFR exome
AF:
0.0000616
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000193
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.000162
AC:
237
AN:
1461800
Hom.:
0
Cov.:
32
AF XY:
0.000149
AC XY:
108
AN XY:
727190
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
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:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53338
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000206
AC:
229
AN:
1112002
Other (OTH)
AF:
0.0000993
AC:
6
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
14
28
43
57
71
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:
0.000138
AC:
21
AN:
152290
Hom.:
0
Cov.:
33
AF XY:
0.000134
AC XY:
10
AN XY:
74466
show subpopulations
African (AFR)
AF:
0.0000481
AC:
2
AN:
41558
American (AMR)
AF:
0.00
AC:
0
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000387
AC:
2
AN:
5172
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000250
AC:
17
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.468
Heterozygous variant carriers
0
1
2
4
5
6
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:
0.000228
Hom.:
1
Bravo
AF:
0.000106
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000741
AC:
9
EpiCase
AF:
0.000164
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Jan 24, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: MYH6 c.2383C>T (p.Arg795Trp) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 9.9e-05 in 251340 control chromosomes. The observed variant frequency is approximately 4 fold of the estimated maximal expected allele frequency for a pathogenic variant in MYH6 causing Cardiomyopathy phenotype (2.5e-05). c.2383C>T has been reported in the literature in an individual affected with hypoplastic left heart syndrome and in a survivor of sudden cardiac arrest due to exercise-related mitral valve prolapse (e.g. Tomita-Mitchell_2016, Asatryan_2019). These report(s) do not provide unequivocal conclusions about association of the variant with Cardiomyopathy. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 27789736, 28082330, 30975432). ClinVar contains an entry for this variant (Variation ID: 470512). Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -

Hypertrophic cardiomyopathy 14 Uncertain:1
Oct 31, 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 tryptophan, which is neutral and slightly polar, at codon 795 of the MYH6 protein (p.Arg795Trp). This variant is present in population databases (rs202120238, gnomAD 0.02%). This missense change has been observed in individual(s) with MYH6-related conditions (PMID: 27789736, 28082330, 30975432). ClinVar contains an entry for this variant (Variation ID: 470512). 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
Sep 07, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiomyopathy Uncertain:1
Aug 02, 2017
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
May 14, 2021
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Reported in a proband with hypoplastic left heart syndrome (Tomita-Mitchell et al., 2016) and in a proband with mitral valve prolapse and a history of sudden cardiac arrest in the published literature (Asatryan et al., 2019); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Reported in ClinVar as a variant of uncertain significance (ClinVar Variant ID# 470512; Landrum et al., 2016); This variant is associated with the following publications: (PMID: 30975432, 27789736) -

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

The p.R795W variant (also known as c.2383C>T), located in coding exon 18 of the MYH6 gene, results from a C to T substitution at nucleotide position 2383. The arginine at codon 795 is replaced by tryptophan, an amino acid with dissimilar properties. This alteration has been reported in a hypoplastic left heart syndrome cohort, but clinical details were limited (Tomita-Mitchell A et al. Physiol. Genomics, 2016 12;48:912-921). This alteration has also been reported in a sudden cardiac arrest cohort (Asatryan B et al. Am J Cardiol, 2019 06;123:2031-2038). This variant was also reported in a pediatric cardiomyopathy cohort (Ware SM et al. Am J Hum Genet, 2022 Feb;109:282-298). 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
0.84
BayesDel_addAF
Pathogenic
0.20
D
BayesDel_noAF
Pathogenic
0.32
CADD
Pathogenic
27
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.90
D;D
Eigen
Uncertain
0.60
Eigen_PC
Uncertain
0.43
FATHMM_MKL
Uncertain
0.89
D
LIST_S2
Uncertain
0.97
D;.
M_CAP
Uncertain
0.23
D
MetaRNN
Pathogenic
0.92
D;D
MetaSVM
Pathogenic
0.92
D
MutationAssessor
Pathogenic
3.9
H;H
PhyloP100
0.74
PrimateAI
Pathogenic
0.82
D
PROVEAN
Pathogenic
-6.2
D;D
REVEL
Pathogenic
0.77
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
1.0
D;D
Vest4
0.94
MVP
0.90
MPC
1.1
ClinPred
0.79
D
GERP RS
4.8
Varity_R
0.42
gMVP
0.96
Mutation Taster
=5/95
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: rs202120238; hg19: chr14-23865539; COSMIC: COSV62449493; COSMIC: COSV62449493; API