18-3215159-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_003803.4(MYOM1):​c.65T>C​(p.Val22Ala) variant causes a missense change. The variant allele was found at a frequency of 0.00000868 in 1,613,658 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000089 ( 0 hom. )

Consequence

MYOM1
NM_003803.4 missense

Scores

2
17

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.26
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.096974045).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYOM1NM_003803.4 linkc.65T>C p.Val22Ala missense_variant Exon 2 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.65T>C p.Val22Ala missense_variant Exon 2 of 38 1 NM_003803.4 ENSP00000348821.4 P52179-1
MYOM1ENST00000261606.11 linkc.65T>C p.Val22Ala missense_variant Exon 2 of 37 1 ENSP00000261606.7 P52179-2
ENSG00000265399ENST00000580139.1 linkn.198-1833A>G intron_variant Intron 2 of 4 2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152226
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000807
AC:
2
AN:
247892
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
134650
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000291
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000891
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000890
AC:
13
AN:
1461432
Hom.:
0
Cov.:
33
AF XY:
0.0000110
AC XY:
8
AN XY:
726966
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000989
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152226
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74372
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.000288
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000378
ExAC
AF:
0.00000826
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
Feb 01, 2025
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.V22A variant (also known as c.65T>C), located in coding exon 1 of the MYOM1 gene, results from a T to C substitution at nucleotide position 65. The valine at codon 22 is replaced by alanine, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated 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
Uncertain
0.46
BayesDel_addAF
Benign
-0.21
T
BayesDel_noAF
Benign
-0.46
CADD
Uncertain
24
DANN
Benign
0.84
DEOGEN2
Benign
0.015
T;.
Eigen
Benign
-0.25
Eigen_PC
Benign
-0.034
FATHMM_MKL
Uncertain
0.90
D
LIST_S2
Benign
0.47
T;T
M_CAP
Benign
0.0069
T
MetaRNN
Benign
0.097
T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
-0.20
N;N
PrimateAI
Benign
0.42
T
PROVEAN
Benign
-0.14
N;N
REVEL
Benign
0.043
Sift
Benign
0.18
T;D
Sift4G
Benign
0.67
T;T
Polyphen
0.0010
B;B
Vest4
0.20
MutPred
0.16
Loss of helix (P = 0.079);Loss of helix (P = 0.079);
MVP
0.74
MPC
0.17
ClinPred
0.11
T
GERP RS
5.7
Varity_R
0.068
gMVP
0.54

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs113162857; hg19: chr18-3215157; API