chr18-3102548-G-A

Variant names:

• chr18-3102548-G-A
• rs374054654
• NM_003803.4:c.3501C>T

Variant summary

Our verdict is Benign. Variant got -9 ACMG points: 2P and 11B. PM2 BP4_Moderate BP6_Very_Strong BP7

The NM_003803.4(MYOM1):​c.3501C>T​(p.Ser1167Ser) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000107 in 1,613,744 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.00050 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000066 (0 hom.)
• Consequence: MYOM1 NM_003803.4 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: 0.915

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 -9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.31).
• BP6: Variant 18-3102548-G-A is Benign according to our data. Variant chr18-3102548-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 525119.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=0.915 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYOM1	NM_003803.4	c.3501C>T	p.Ser1167Ser	synonymous_variant	Exon 23 of 38	ENST00000356443.9	NP_003794.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYOM1	ENST00000356443.9	c.3501C>T	p.Ser1167Ser	synonymous_variant	Exon 23 of 38	1	NM_003803.4	ENSP00000348821.4
MYOM1	ENST00000261606.11	c.3213C>T	p.Ser1071Ser	synonymous_variant	Exon 22 of 37	1		ENSP00000261606.7

Frequencies

GnomAD3 genomes AF: 0.000493 AC: 75 AN: 152020 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00155

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000262

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000208

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000588

Gnomad OTH AF: 0.000957

GnomAD3 exomes AF: 0.000136 AC: 34 AN: 249172 Hom.: 0 AF XY: 0.000148 AC XY: 20 AN XY: 135176

Gnomad AFR exome AF: 0.00129

Gnomad AMR exome AF: 0.0000870

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.000131

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000531

Gnomad OTH exome AF: 0.000165

GnomAD4 exome AF: 0.0000657 AC: 96 AN: 1461606 Hom.: 0 Cov.: 31 AF XY: 0.0000701 AC XY: 51 AN XY: 727084

Gnomad4 AFR exome AF: 0.00108

Gnomad4 AMR exome AF: 0.000134

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000580

Gnomad4 FIN exome AF: 0.0000187

Gnomad4 NFE exome AF: 0.0000351

Gnomad4 OTH exome AF: 0.000133

GnomAD4 genome AF: 0.000500 AC: 76 AN: 152138 Hom.: 0 Cov.: 32 AF XY: 0.000511 AC XY: 38 AN XY: 74372

Gnomad4 AFR AF: 0.00157

Gnomad4 AMR AF: 0.000262

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000208

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000588

Gnomad4 OTH AF: 0.000947

Alfa AF: 0.000280 Hom.: 0

Bravo AF: 0.000574

EpiCase AF: 0.0000545

EpiControl AF: 0.000119

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:1

Mar 12, 2022

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. -

Hypertrophic cardiomyopathy Benign:1

Jan 22, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.31
CADD	Benign	8.5
DANN	Benign	0.63

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: rs374054654; hg19: chr18-3102546;