rs765511668

Positions:

chr18-3193840-T-G

Variant summary

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

The NM_003803.4(MYOM1):c.409A>C(p.Met137Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000821 in 1,461,488 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

MYOM1
NM_003803.4 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 0.189

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:

MYOM1 (HGNC:):

MYOM1 links:

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=0.12307352).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MYOM1	NM_003803.4 linkuse as main transcript	c.409A>C	p.Met137Leu	missense_variant	3/38	ENST00000356443.9	NP_003794.3	P52179-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	UniProt
MYOM1	ENST00000356443.9 linkuse as main transcript	c.409A>C	p.Met137Leu	missense_variant	3/38	1	NM_003803.4	ENSP00000348821.4	P52179-1
MYOM1	ENST00000261606.11 linkuse as main transcript	c.409A>C	p.Met137Leu	missense_variant	3/37	1		ENSP00000261606.7	P52179-2
ENSG00000265399	ENST00000580139.1 linkuse as main transcript	n.121-36T>G		intron_variant		2

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.0000362

AC:

AN:

248934

Hom.:

AF XY:

0.0000296

AC XY:

AN XY:

135048

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000501

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000821

AC:

AN:

1461488

Hom.:

Cov.:

AF XY:

0.00000550

AC XY:

AN XY:

727008

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000277

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

8.99e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Bravo

AF:

0.0000151

ExAC

AF:

0.00000828

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

Jun 23, 2023

The p.M137L variant (also known as c.409A>C), located in coding exon 2 of the MYOM1 gene, results from an A to C substitution at nucleotide position 409. The methionine at codon 137 is replaced by leucine, an amino acid with highly 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. -

Hypertrophic cardiomyopathy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 23, 2019

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 missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The leucine amino acid residue is found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with MYOM1-related disease. This variant is present in population databases (rs765511668, ExAC 0.01%). This sequence change replaces methionine with leucine at codon 137 of the MYOM1 protein (p.Met137Leu). The methionine residue is weakly conserved and there is a small physicochemical difference between methionine and leucine. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.23

BayesDel_addAF

Benign

-0.41

BayesDel_noAF

Benign

-0.49

CADD

Benign

DANN

Benign

0.81

DEOGEN2

Benign

0.023

T;.;.

Eigen

Benign

-0.84

Eigen_PC

Benign

-0.71

FATHMM_MKL

Benign

0.16

LIST_S2

Benign

0.61

T;D;T

M_CAP

Benign

0.011

MetaRNN

Benign

0.071

T;T;T

MetaSVM

Benign

-1.1

MutationAssessor

Benign

1.9

L;.;L

PrimateAI

Benign

0.29

PROVEAN

Benign

-0.42

N;N;N

REVEL

Benign

0.032

Sift

Benign

0.58

T;D;T

Sift4G

Benign

0.41

T;T;T

Polyphen

0.0

B;.;B

Vest4

0.20

MutPred

0.35

Loss of sheet (P = 0.1158);.;Loss of sheet (P = 0.1158);

MVP

0.60

MPC

0.13

ClinPred

0.023

GERP RS

-1.9

Varity_R

0.033

gMVP

0.31

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