rs376804166

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP3

The NM_003803.4(MYOM1):c.3914T>C(p.Met1305Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000266 in 1,613,832 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 31)

Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

MYOM1
NM_003803.4 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 9.32

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 3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.822

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYOM1	NM_003803.4 linkuse as main transcript	c.3914T>C	p.Met1305Thr	missense_variant	27/38	ENST00000356443.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYOM1	ENST00000356443.9 linkuse as main transcript	c.3914T>C	p.Met1305Thr	missense_variant	27/38	1	NM_003803.4	P2	P52179-1
MYOM1	ENST00000261606.11 linkuse as main transcript	c.3626T>C	p.Met1209Thr	missense_variant	26/37	1		A2	P52179-2
MYOM1	ENST00000581075.1 linkuse as main transcript	c.14T>C	p.Met5Thr	missense_variant, NMD_transcript_variant	1/8	5

Frequencies

GnomAD3 genomes

AF:

0.0000394

AC:

AN:

152146

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

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:

0.0000588

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000401

AC:

AN:

249228

Hom.:

AF XY:

0.0000444

AC XY:

AN XY:

135204

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000869

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:

0.0000531

Gnomad OTH exome

AF:

0.000165

GnomAD4 exome

AF:

0.0000253

AC:

AN:

1461686

Hom.:

Cov.:

AF XY:

0.0000303

AC XY:

AN XY:

727126

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000894

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:

0.0000225

Gnomad4 OTH exome

AF:

0.0000497

GnomAD4 genome

AF:

0.0000394

AC:

AN:

152146

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74324

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000588

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000564

Hom.:

Bravo

AF:

0.0000567

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000121

AC:

ExAC

AF:

0.0000496

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.000178

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

Jul 14, 2023

The p.M1305T variant (also known as c.3914T>C), located in coding exon 26 of the MYOM1 gene, results from a T to C substitution at nucleotide position 3914. The methionine at codon 1305 is replaced by threonine, an amino acid with similar 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

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 24, 2023

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. 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. ClinVar contains an entry for this variant (Variation ID: 581247). This variant has not been reported in the literature in individuals affected with MYOM1-related conditions. This variant is present in population databases (rs376804166, gnomAD 0.01%). This sequence change replaces methionine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 1305 of the MYOM1 protein (p.Met1305Thr). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.82

BayesDel_addAF

Uncertain

0.091

BayesDel_noAF

Uncertain

0.090

Cadd

Uncertain

Dann

Uncertain

0.99

DEOGEN2

Benign

0.26

T;.;.

Eigen

Pathogenic

0.86

Eigen_PC

Pathogenic

0.84

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.90

D;D;D

M_CAP

Benign

0.039

MetaRNN

Pathogenic

0.82

D;D;D

MetaSVM

Benign

-1.2

MutationAssessor

Uncertain

2.5

M;.;.

MutationTaster

Benign

1.0

D;D;D

PrimateAI

Uncertain

0.62

PROVEAN

Pathogenic

-4.8

D;.;D

REVEL

Uncertain

0.59

Sift

Benign

0.092

T;.;D

Sift4G

Uncertain

0.0060

D;D;D

Polyphen

1.0

D;.;D

Vest4

0.91

MVP

0.80

MPC

0.66

ClinPred

0.61

GERP RS

5.7

Varity_R

0.82

gMVP

0.74

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