chr18-3188980-G-A

Variant names:

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_003803.4(MYOM1):c.539C>T(p.Thr180Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00103 in 1,613,420 control chromosomes in the GnomAD database, including 10 homozygotes. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

Frequency

Genomes: 𝑓 0.0056 ( 8 hom., cov: 31)

Exomes 𝑓: 0.00056 ( 2 hom. )

Consequence

MYOM1
NM_003803.4 missense

Scores

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:4

Conservation

PhyloP100: 1.70

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 Benign. Variant got -20 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.0031106174).

BP6

Variant 18-3188980-G-A is Benign according to our data. Variant chr18-3188980-G-A is described in ClinVar as [Benign]. Clinvar id is 226829.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.0056 (850/151726) while in subpopulation AFR AF= 0.0189 (780/41348). AF 95% confidence interval is 0.0178. There are 8 homozygotes in gnomad4. There are 406 alleles in male gnomad4 subpopulation. Median coverage is 31. This position pass quality control queck.

BS2

High Homozygotes in GnomAd4 at 8 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYOM1	NM_003803.4 link	c.539C>T	p.Thr180Ile	missense_variant	Exon 4 of 38	ENST00000356443.9	NP_003794.3	P52179-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYOM1	ENST00000356443.9 link	c.539C>T	p.Thr180Ile	missense_variant	Exon 4 of 38	1	NM_003803.4	ENSP00000348821.4		P52179-1
MYOM1	ENST00000261606.11 link	c.539C>T	p.Thr180Ile	missense_variant	Exon 4 of 37	1		ENSP00000261606.7		P52179-2

Frequencies

GnomAD3 genomes

AF:

0.00560

AC:

849

AN:

151608

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0189

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00336

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:

0.000162

Gnomad OTH

AF:

0.00383

GnomAD3 exomes

AF:

0.00137

AC:

341

AN:

249234

Hom.:

AF XY:

0.00105

AC XY:

142

AN XY:

135216

show subpopulations

Gnomad AFR exome

AF:

0.0178

Gnomad AMR exome

AF:

0.00165

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:

0.0000620

Gnomad OTH exome

AF:

0.000330

GnomAD4 exome

AF:

0.000558

AC:

815

AN:

1461694

Hom.:

Cov.:

AF XY:

0.000466

AC XY:

339

AN XY:

727130

show subpopulations

Gnomad4 AFR exome

AF:

0.0171

Gnomad4 AMR exome

AF:

0.00181

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:

0.0000540

Gnomad4 OTH exome

AF:

0.00162

GnomAD4 genome

AF:

0.00560

AC:

850

AN:

151726

Hom.:

Cov.:

AF XY:

0.00548

AC XY:

406

AN XY:

74142

show subpopulations

Gnomad4 AFR

AF:

0.0189

Gnomad4 AMR

AF:

0.00335

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000162

Gnomad4 OTH

AF:

0.00379

Alfa

AF:

0.000972

Hom.:

Bravo

AF:

0.00660

ESP6500AA

AF:

0.0140

AC:

ESP6500EA

AF:

0.000240

AC:

ExAC

AF:

0.00143

AC:

173

Asia WGS

AF:

0.000866

AC:

AN:

3478

ClinVar

Significance: Benign

Submissions summary: Benign:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:1

Benign, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Nov 24, 2014

Thr180Ile in exon 4 of MYOM1: This variant is not expected to have clinical sign ificance because it has been identified in 1.4% (56/3988) of African American ch romosomes from a broad population by the NHLBI Exome Sequencing Project (http:// evs.gs.washington.edu/EVS; dbSNP rs61735396). -

not provided

Benign:1

Benign, criteria provided, single submitter

not provided

Breakthrough Genomics, Breakthrough Genomics

- -

Hypertrophic cardiomyopathy

Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 31, 2025

- -

Cardiovascular phenotype

Benign:1

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 21, 2013

General population or subpopulation frequency is too high to be a pathogenic mutation based on disease/syndrome prevalence and penetrance -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.29

BayesDel_addAF

Benign

-0.61

BayesDel_noAF

Benign

-0.63

CADD

Benign

DANN

Uncertain

0.99

DEOGEN2

Benign

0.019

T;.;.

Eigen

Benign

-0.64

Eigen_PC

Benign

-0.55

FATHMM_MKL

Benign

0.049

LIST_S2

Benign

0.71

T;T;T

MetaRNN

Benign

0.0031

T;T;T

MetaSVM

Benign

-1.1

MutationAssessor

Benign

1.0

L;.;L

PrimateAI

Benign

0.33

PROVEAN

Benign

-0.41

N;N;N

REVEL

Benign

0.058

Sift

Benign

0.049

D;D;T

Sift4G

Uncertain

0.054

T;T;T

Polyphen

0.019

B;.;B

Vest4

0.10

MVP

0.63

MPC

0.15

ClinPred

0.0038

GERP RS

4.1

Varity_R

0.076

gMVP

0.085

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