rs371861150

chr18-3151734-G-Achr18-3151734-G-C

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP4_Strong BP6_Very_Strong BP7

The NM_003803.4(MYOM1):c.1803C>T(p.Pro601=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000243 in 1,613,720 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. P601P) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.0014 (2 hom., cov: 32)
  • Exomes 𝑓: 0.00012 (0 hom.)
• Consequence: MYOM1 NM_003803.4 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:4
• Conservation: PhyloP100: -2.16

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]

ACMG classification

Verdict is Benign. Variant got -13 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.77).
• BP6: Variant 18-3151734-G-A is Benign according to our data. Variant chr18-3151734-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 226804.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=-2.16 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYOM1	NM_003803.4	c.1803C>T	p.Pro601=	synonymous_variant	12/38	ENST00000356443.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYOM1	ENST00000356443.9	c.1803C>T	p.Pro601=	synonymous_variant	12/38	1	NM_003803.4	P2
MYOM1	ENST00000261606.11	c.1803C>T	p.Pro601=	synonymous_variant	12/37	1		A2

Frequencies

GnomAD3 genomes AF: 0.00135 AC: 205 AN: 152106 Hom.: 1 Cov.: 32

Gnomad AFR AF: 0.00466

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000720

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000277 AC: 69 AN: 249086 Hom.: 0 AF XY: 0.000229 AC XY: 31 AN XY: 135146

Gnomad AFR exome AF: 0.00375

Gnomad AMR exome AF: 0.000174

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: 0.0000177

Gnomad OTH exome AF: 0.000497

GnomAD4 exome AF: 0.000124 AC: 181 AN: 1461498 Hom.: 0 Cov.: 30 AF XY: 0.000105 AC XY: 76 AN XY: 727030

Gnomad4 AFR exome AF: 0.00430

Gnomad4 AMR exome AF: 0.000134

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000540

Gnomad4 OTH exome AF: 0.000331

GnomAD4 genome AF: 0.00139 AC: 211 AN: 152222 Hom.: 2 Cov.: 32 AF XY: 0.00152 AC XY: 113 AN XY: 74416

Gnomad4 AFR AF: 0.00479

Gnomad4 AMR AF: 0.000719

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000691 Hom.: 0

Bravo AF: 0.00144

Asia WGS AF: 0.000577 AC: 2 AN: 3478

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:2

Benign, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Nov 24, 2014	Pro601Pro in exon 12 of MYOM1: This variant is not expected to have clinical sig nificance because it does not alter an amino acid residue and is not located wit hin the splice consensus sequence. It has been identified in 0.4% (17/3778) of A frican American chromosomes from a broad population by the NHLBI Exome Sequencin g Project (http://evs.gs.washington.edu/EVS). -
Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Feb 12, 2022	This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

MYOM1-related disorder Benign:1

Likely benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Mar 12, 2019

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Hypertrophic cardiomyopathy Benign:1

Benign, criteria provided, single submitter

clinical testing

Invitae

Jan 24, 2024

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.77
Cadd	Benign	0.28
Dann	Benign	0.91

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

Other links and lift over

dbSNP: rs371861150; hg19: chr18-3151732;