NM_017534.6:c.3358C>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_017534.6(MYH2):​c.3358C>T​(p.Arg1120Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000124 in 1,614,076 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/22 in silico tools predict a damaging 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. R1120H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

MYH2
NM_017534.6 missense

Scores

15
3
1

Clinical Significance

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

Conservation

PhyloP100: 9.61

Publications

0 publications found
Variant links:
Genes affected
MYH2 (HGNC:7572): (myosin heavy chain 2) Myosins are actin-based motor proteins that function in the generation of mechanical force in eukaryotic cells. Muscle myosins are heterohexamers composed of 2 myosin heavy chains and 2 pairs of nonidentical myosin light chains. This gene encodes a member of the class II or conventional myosin heavy chains, and functions in skeletal muscle contraction. This gene is found in a cluster of myosin heavy chain genes on chromosome 17. A mutation in this gene results in inclusion body myopathy-3. Multiple alternatively spliced variants, encoding the same protein, have been identified. [provided by RefSeq, Sep 2009]
MYHAS (HGNC:50609): (myosin heavy chain gene cluster antisense RNA) Predicted to enable primary miRNA binding activity. Predicted to be involved in response to muscle activity and skeletal muscle fiber development. Predicted to act upstream of or within with a positive effect on gene expression. Predicted to be located in cytoplasm and nucleus. [provided by Alliance of Genome Resources, Apr 2022]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.91

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYH2NM_017534.6 linkc.3358C>T p.Arg1120Cys missense_variant Exon 27 of 40 ENST00000245503.10 NP_060004.3 Q9UKX2-1
MYH2NM_001100112.2 linkc.3358C>T p.Arg1120Cys missense_variant Exon 27 of 40 NP_001093582.1 Q9UKX2-1
MYHASNR_125367.1 linkn.168-38461G>A intron_variant Intron 2 of 10

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYH2ENST00000245503.10 linkc.3358C>T p.Arg1120Cys missense_variant Exon 27 of 40 1 NM_017534.6 ENSP00000245503.5 Q9UKX2-1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152190
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000798
AC:
2
AN:
250632
AF XY:
0.00000737
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:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000116
AC:
17
AN:
1461886
Hom.:
0
Cov.:
32
AF XY:
0.0000110
AC XY:
8
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000117
AC:
13
AN:
1112006
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.478
Heterozygous variant carriers
0
2
4
6
8
10
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152190
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74348
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41446
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000712
Hom.:
0
Bravo
AF:
0.0000453
ExAC
AF:
0.00000824
AC:
1

ClinVar

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

Submissions by phenotype

Myopathy, proximal, and ophthalmoplegia Uncertain:2
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Jan 31, 2025
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 1120 of the MYH2 protein (p.Arg1120Cys). This variant is present in population databases (rs756255059, gnomAD 0.002%). This variant has not been reported in the literature in individuals affected with MYH2-related conditions. ClinVar contains an entry for this variant (Variation ID: 321675). 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 not expected to disrupt MYH2 protein function with a negative 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. -

Inclusion Body Myopathy, Dominant Uncertain:1
Jun 14, 2016
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.59
BayesDel_addAF
Pathogenic
0.36
D
BayesDel_noAF
Pathogenic
0.29
CADD
Pathogenic
30
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.67
D;D
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.95
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Uncertain
0.96
.;D
M_CAP
Pathogenic
0.35
D
MetaRNN
Pathogenic
0.91
D;D
MetaSVM
Pathogenic
0.91
D
MutationAssessor
Pathogenic
3.5
H;H
PhyloP100
9.6
PrimateAI
Pathogenic
0.84
D
PROVEAN
Pathogenic
-6.0
D;D
REVEL
Pathogenic
0.86
Sift
Uncertain
0.0080
D;D
Sift4G
Pathogenic
0.0010
D;D
Polyphen
0.99
D;D
Vest4
0.86
MutPred
0.57
Loss of MoRF binding (P = 0.0159);Loss of MoRF binding (P = 0.0159);
MVP
0.94
MPC
0.59
ClinPred
0.96
D
GERP RS
5.1
Varity_R
0.33
gMVP
0.23
Mutation Taster
=9/91
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: rs756255059; hg19: chr17-10432393; COSMIC: COSV55433110; API