rs749676865

Variant summary

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

The NM_003803.4(MYOM1):​c.3278C>T​(p.Ala1093Val) variant causes a missense change. The variant allele was found at a frequency of 0.0000267 in 1,611,896 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A1093A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000025 ( 1 hom. )

Consequence

MYOM1
NM_003803.4 missense

Scores

2
17

Clinical Significance

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

Conservation

PhyloP100: 4.66

Publications

0 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=0.15857041).
BS2
High AC in GnomAd4 at 7 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYOM1NM_003803.4 linkc.3278C>T p.Ala1093Val missense_variant Exon 21 of 38 ENST00000356443.9 NP_003794.3 P52179-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYOM1ENST00000356443.9 linkc.3278C>T p.Ala1093Val missense_variant Exon 21 of 38 1 NM_003803.4 ENSP00000348821.4 P52179-1
MYOM1ENST00000261606.11 linkc.2990C>T p.Ala997Val missense_variant Exon 20 of 37 1 ENSP00000261606.7 P52179-2

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152150
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000242
AC:
6
AN:
247674
AF XY:
0.0000223
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:
0.0000357
Gnomad OTH exome
AF:
0.000166
GnomAD4 exome
AF:
0.0000247
AC:
36
AN:
1459746
Hom.:
1
Cov.:
30
AF XY:
0.0000234
AC XY:
17
AN XY:
726114
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33428
American (AMR)
AF:
0.0000224
AC:
1
AN:
44634
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26114
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39686
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86026
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53358
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4640
European-Non Finnish (NFE)
AF:
0.0000288
AC:
32
AN:
1111624
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60236
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.485
Heterozygous variant carriers
0
3
6
10
13
16
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:
0.0000460
AC:
7
AN:
152150
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74332
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41434
American (AMR)
AF:
0.0000655
AC:
1
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68014
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.489
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000579
Hom.:
0
Bravo
AF:
0.0000453
ExAC
AF:
0.0000331
AC:
4
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

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

Submissions by phenotype

not specified Uncertain:2
Nov 12, 2015
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.Ala1093Val variant in MYOM1 has not been previously reported in individual s with cardiomyopathy, but has been identified in 3/58954 European chromosomes b y the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs749676865). Alanine (Ala) at position 1093 is not conserved in mammals or evol utionarily distant species and 2 mammals (black flying fox, megabat) carry a val ine (Val) at this position, raising the possibility that this change may be tole rated. In summary, the clinical significance of the p.Ala1093Val variant is unce rtain. -

Jan 23, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.3278C>T (p.A1093V) alteration is located in exon 21 (coding exon 20) of the MYOM1 gene. This alteration results from a C to T substitution at nucleotide position 3278, causing the alanine (A) at amino acid position 1093 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Hypertrophic cardiomyopathy Uncertain:1
Apr 09, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The valine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect 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. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. ClinVar contains an entry for this variant (Variation ID: 229021). This variant has not been reported in the literature in individuals affected with MYOM1-related conditions. This variant is present in population databases (rs749676865, gnomAD 0.004%). This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 1093 of the MYOM1 protein (p.Ala1093Val). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.27
BayesDel_addAF
Benign
-0.27
T
BayesDel_noAF
Benign
-0.50
CADD
Benign
21
DANN
Uncertain
0.98
DEOGEN2
Benign
0.044
T;.;.
Eigen
Benign
-0.51
Eigen_PC
Benign
-0.44
FATHMM_MKL
Uncertain
0.82
D
LIST_S2
Benign
0.76
T;T;T
M_CAP
Benign
0.017
T
MetaRNN
Benign
0.16
T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
-0.050
N;.;.
PhyloP100
4.7
PrimateAI
Benign
0.35
T
PROVEAN
Benign
-1.5
N;.;N
REVEL
Benign
0.16
Sift
Benign
0.24
T;.;T
Sift4G
Benign
0.15
T;T;T
Polyphen
0.71
P;.;B
Vest4
0.24
MVP
0.75
MPC
0.14
ClinPred
0.24
T
GERP RS
2.0
Varity_R
0.047
gMVP
0.21
Mutation Taster
=89/11
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs749676865; hg19: chr18-3116354; API