rs372294428

chr18-3116505-G-A

Variant summary

Our verdict is Benign. Variant got -11 ACMG points: 2P and 13B. PM2 BP4_Strong BP6_Very_Strong BP7

The NM_003803.4(MYOM1):c.3129C>T(p.His1043=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000425 in 1,554,334 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 0.000033 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000044 (0 hom.)
• Consequence: MYOM1 NM_003803.4 synonymous
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: 0.364

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 -11 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.66).
• BP6: Variant 18-3116505-G-A is Benign according to our data. Variant chr18-3116505-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 416050.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=0.364 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYOM1	NM_003803.4	c.3129C>T	p.His1043=	synonymous_variant	21/38	ENST00000356443.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYOM1	ENST00000356443.9	c.3129C>T	p.His1043=	synonymous_variant	21/38	1	NM_003803.4	P2
MYOM1	ENST00000261606.11	c.2841C>T	p.His947=	synonymous_variant	20/37	1		A2

Frequencies

GnomAD3 genomes AF: 0.0000329 AC: 5 AN: 152190 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00316

Gnomad NFE AF: 0.0000294

Gnomad OTH AF: 0.000478

GnomAD3 exomes AF: 0.0000700 AC: 15 AN: 214328 Hom.: 0 AF XY: 0.0000515 AC XY: 6 AN XY: 116570

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000152

Gnomad ASJ exome AF: 0.000138

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.000125

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000692

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000435 AC: 61 AN: 1402144 Hom.: 0 Cov.: 30 AF XY: 0.0000405 AC XY: 28 AN XY: 692202

Gnomad4 AFR exome AF: 0.0000956

Gnomad4 AMR exome AF: 0.000136

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000142

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000296

Gnomad4 OTH exome AF: 0.0000868

GnomAD4 genome AF: 0.0000329 AC: 5 AN: 152190 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74344

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000654

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.000478

Alfa AF: 0.000122 Hom.: 0

Bravo AF: 0.0000718

ClinVar

Significance: Likely benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 25, 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. -

Hypertrophic cardiomyopathy Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Apr 24, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.66
Cadd	Benign	0.41
Dann	Benign	0.40

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: rs372294428; hg19: chr18-3116503;