18-3102510-T-G

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_003803.4(MYOM1):​c.3539A>C​(p.Asp1180Ala) variant causes a missense change. The variant allele was found at a frequency of 0.0000236 in 1,613,178 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign 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. D1180G) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

MYOM1
NM_003803.4 missense

Scores

3
8
7

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 5.16

Publications

1 publications found
Variant links:
Genes affected
MYOM1 (HGNC:7613): (myomesin 1) The giant protein titin, together with its associated proteins, interconnects the major structure of sarcomeres, the M bands and Z discs. The C-terminal end of the titin string extends into the M line, where it binds tightly to M-band constituents of apparent molecular masses of 190 kD (myomesin 1) and 165 kD (myomesin 2). This protein, myomesin 1, like myomesin 2, titin, and other myofibrillar proteins contains structural modules with strong homology to either fibronectin type III (motif I) or immunoglobulin C2 (motif II) domains. Myomesin 1 and myomesin 2 each have a unique N-terminal region followed by 12 modules of motif I or motif II, in the arrangement II-II-I-I-I-I-I-II-II-II-II-II. The two proteins share 50% sequence identity in this repeat-containing region. The head structure formed by these 2 proteins on one end of the titin string extends into the center of the M band. The integrating structure of the sarcomere arises from muscle-specific members of the superfamily of immunoglobulin-like proteins. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jul 2008]
MYOM1 Gene-Disease associations (from GenCC):
  • hypertrophic cardiomyopathy
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.23249093).
BS2
High AC in GnomAdExome4 at 34 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003803.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
MYOM1
NM_003803.4
MANE Select
c.3539A>Cp.Asp1180Ala
missense
Exon 23 of 38NP_003794.3
MYOM1
NM_019856.2
c.3251A>Cp.Asp1084Ala
missense
Exon 22 of 37NP_062830.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
MYOM1
ENST00000356443.9
TSL:1 MANE Select
c.3539A>Cp.Asp1180Ala
missense
Exon 23 of 38ENSP00000348821.4
MYOM1
ENST00000261606.11
TSL:1
c.3251A>Cp.Asp1084Ala
missense
Exon 22 of 37ENSP00000261606.7

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
151836
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:
0.000580
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000643
AC:
16
AN:
248984
AF XY:
0.0000666
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000724
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000233
AC:
34
AN:
1461342
Hom.:
0
Cov.:
30
AF XY:
0.0000303
AC XY:
22
AN XY:
726974
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33464
American (AMR)
AF:
0.00
AC:
0
AN:
44660
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26124
East Asian (EAS)
AF:
0.000227
AC:
9
AN:
39684
South Asian (SAS)
AF:
0.000186
AC:
16
AN:
86200
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53390
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1111704
Other (OTH)
AF:
0.000116
AC:
7
AN:
60348
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
1
3
4
6
7
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:
0.0000263
AC:
4
AN:
151836
Hom.:
0
Cov.:
32
AF XY:
0.0000405
AC XY:
3
AN XY:
74152
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41298
American (AMR)
AF:
0.00
AC:
0
AN:
15230
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3460
East Asian (EAS)
AF:
0.000580
AC:
3
AN:
5170
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10574
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67966
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
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:
0.00
Hom.:
1
Bravo
AF:
0.0000189
ExAC
AF:
0.0000662
AC:
8

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
May 26, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.D1180A variant (also known as c.3539A>C), located in coding exon 22 of the MYOM1 gene, results from an A to C substitution at nucleotide position 3539. The aspartic acid at codon 1180 is replaced by alanine, an amino acid with dissimilar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Hypertrophic cardiomyopathy Uncertain:1
Jan 30, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with alanine, which is neutral and non-polar, at codon 1180 of the MYOM1 protein (p.Asp1180Ala). This variant is present in population databases (rs188319622, gnomAD 0.07%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individual(s) with MYOM1-related conditions (internal data). ClinVar contains an entry for this variant (Variation ID: 654555). 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) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on MYOM1 protein function. 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.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.37
BayesDel_addAF
Benign
-0.15
T
BayesDel_noAF
Uncertain
-0.080
CADD
Benign
22
DANN
Uncertain
0.99
DEOGEN2
Benign
0.29
T
Eigen
Uncertain
0.62
Eigen_PC
Uncertain
0.57
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.77
T
M_CAP
Benign
0.037
D
MetaRNN
Benign
0.23
T
MetaSVM
Uncertain
-0.22
T
MutationAssessor
Pathogenic
3.0
M
PhyloP100
5.2
PrimateAI
Benign
0.39
T
PROVEAN
Pathogenic
-6.7
D
REVEL
Benign
0.26
Sift
Uncertain
0.0020
D
Sift4G
Uncertain
0.0030
D
Polyphen
1.0
D
Vest4
0.53
MutPred
0.23
Loss of phosphorylation at T1178 (P = 0.1189)
MVP
0.92
MPC
0.32
ClinPred
0.43
T
GERP RS
5.5
Varity_R
0.70
gMVP
0.77
Mutation Taster
=45/55
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs188319622; hg19: chr18-3102508; API