chr11-47337708-C-CA

Position:

• chr11-47337708-C-CA

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000256.3(MYBPC3):​c.2394_2395insT​(p.Gly799TrpfsTer34) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. D798D) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 31)
• Consequence: MYBPC3 NM_000256.3 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: -0.286

Genes affected

MYBPC3 (HGNC:7551): (myosin binding protein C3) MYBPC3 encodes the cardiac isoform of myosin-binding protein C. Myosin-binding protein C is a myosin-associated protein found in the cross-bridge-bearing zone (C region) of A bands in striated muscle. MYBPC3 is expressed exclusively in heart muscle and is a key regulator of cardiac contraction. Mutations in this gene are a frequent cause of familial hypertrophic cardiomyopathy. [provided by RefSeq, May 2022]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-47337708-C-CA is Pathogenic according to our data. Variant chr11-47337708-C-CA is described in ClinVar as [Likely_pathogenic]. Clinvar id is 177862.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYBPC3	NM_000256.3	c.2394_2395insT	p.Gly799TrpfsTer34	frameshift_variant	24/35	ENST00000545968.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYBPC3	ENST00000545968.6	c.2394_2395insT	p.Gly799TrpfsTer34	frameshift_variant	24/35	5	NM_000256.3	P4
MYBPC3	ENST00000399249.6	c.2394_2395insT	p.Gly799TrpfsTer34	frameshift_variant	23/34	5		A2
MYBPC3	ENST00000544791.1	c.2394_2395insT	p.Gly799TrpfsTer9	frameshift_variant, NMD_transcript_variant	24/27	5

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypertrophic cardiomyopathy Pathogenic:2

Pathogenic, no assertion criteria provided	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Mar 05, 2013	proposed classification - variant undergoing re-assessment, contact laboratory -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Nov 14, 2015	For these reasons, this variant has been classified as Pathogenic. While this particular variant has not been reported in the literature, truncating variants in MYBPC3 are known to be pathogenic (PMID: 19574547). This sequence change inserts 1 nucleotide in exon 24 of the MYBPC3 mRNA (c.2394dupT), causing a frameshift at codon 799. This creates a premature translational stop signal (p.Gly799Trpfs*34) and is expected to result in an absent or disrupted protein product. -

Hypertrophic cardiomyopathy 4 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Laboratory of Genetics and Molecular Cardiology, University of São Paulo

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Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs730880341; hg19: chr11-47359259;