18-3126841-C-A

Position:

chr18-3126841-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The ENST00000356443.9(MYOM1):c.2851G>T(p.Val951Phe) variant causes a missense change. The variant allele was found at a frequency of 0.0000304 in 1,613,422 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. V951L) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00020 ( 0 hom., cov: 30)

Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

MYOM1
ENST00000356443.9 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 5.86

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MYOM1	NM_003803.4 linkuse as main transcript	c.2851G>T	p.Val951Phe	missense_variant	19/38	ENST00000356443.9	NP_003794.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MYOM1	ENST00000356443.9 linkuse as main transcript	c.2851G>T	p.Val951Phe	missense_variant	19/38	1	NM_003803.4	ENSP00000348821	P2	P52179-1
MYOM1	ENST00000261606.11 linkuse as main transcript	c.2563G>T	p.Val855Phe	missense_variant	18/37	1		ENSP00000261606	A2	P52179-2
MYOM1	ENST00000582016.1 linkuse as main transcript	n.407G>T		non_coding_transcript_exon_variant	2/3	4

Frequencies

GnomAD3 genomes

AF:

0.000197

AC:

AN:

152178

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000724

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000524

AC:

AN:

248034

Hom.:

AF XY:

0.0000372

AC XY:

AN XY:

134540

show subpopulations

Gnomad AFR exome

AF:

0.000649

Gnomad AMR exome

AF:

0.00

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:

0.0000178

Gnomad OTH exome

AF:

0.000166

GnomAD4 exome

AF:

0.0000130

AC:

AN:

1461126

Hom.:

Cov.:

AF XY:

0.0000124

AC XY:

AN XY:

726762

show subpopulations

Gnomad4 AFR exome

AF:

0.000448

Gnomad4 AMR exome

AF:

0.00

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:

0.00000180

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.000197

AC:

AN:

152296

Hom.:

Cov.:

AF XY:

0.000201

AC XY:

AN XY:

74460

show subpopulations

Gnomad4 AFR

AF:

0.000722

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

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

Alfa

AF:

0.0000658

Hom.:

Bravo

AF:

0.000200

ExAC

AF:

0.0000745

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 02, 2024

The c.2851G>T (p.V951F) alteration is located in exon 19 (coding exon 18) of the MYOM1 gene. This alteration results from a G to T substitution at nucleotide position 2851, causing the valine (V) at amino acid position 951 to be replaced by a phenylalanine (F). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Hypertrophic cardiomyopathy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 17, 2023

This sequence change replaces valine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 951 of the MYOM1 protein (p.Val951Phe). This variant is present in population databases (rs573023709, gnomAD 0.07%), and has an allele count higher than expected for a pathogenic variant. This variant has not been reported in the literature in individuals affected with MYOM1-related conditions. ClinVar contains an entry for this variant (Variation ID: 410257). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt MYOM1 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.50

BayesDel_addAF

Uncertain

0.022

BayesDel_noAF

Pathogenic

0.16

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.20

T;.;.

Eigen

Uncertain

0.68

Eigen_PC

Uncertain

0.63

FATHMM_MKL

Uncertain

0.95

LIST_S2

Uncertain

0.96

D;D;D

M_CAP

Benign

0.056

MetaRNN

Uncertain

0.63

D;D;D

MetaSVM

Uncertain

-0.26

MutationAssessor

Uncertain

2.9

M;.;.

MutationTaster

Benign

1.0

D;D;D

PrimateAI

Uncertain

0.62

PROVEAN

Uncertain

-3.9

D;.;D

REVEL

Uncertain

0.41

Sift

Uncertain

0.0010

D;.;D

Sift4G

Uncertain

0.0060

D;D;D

Polyphen

1.0

D;.;D

Vest4

0.85

MVP

0.90

MPC

0.71

ClinPred

0.97

GERP RS

4.6

Varity_R

0.78

gMVP

0.83

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

LitVar

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

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over