rs730880719

Variant names:

• chr11-47333196-TG-T
• rs730880719
• NM_000256.3:c.3327delC

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.3327delC​(p.Met1110TrpfsTer79) 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 Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MYBPC3 NM_000256.3 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 1.35

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 11-47333196-TG-T is Pathogenic according to our data. Variant chr11-47333196-TG-T is described in ClinVar as [Pathogenic]. Clinvar id is 181155.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYBPC3	NM_000256.3	c.3327delC	p.Met1110TrpfsTer79	frameshift_variant	Exon 30 of 35	ENST00000545968.6	NP_000247.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYBPC3	ENST00000545968.6	c.3327delC	p.Met1110TrpfsTer79	frameshift_variant	Exon 30 of 35	5	NM_000256.3	ENSP00000442795.1
MYBPC3	ENST00000399249.6	c.3327delC	p.Met1110TrpfsTer79	frameshift_variant	Exon 29 of 34	5		ENSP00000382193.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Cardiomyopathy Pathogenic:1

Dec 20, 2011

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

A deletion of a single “C” nucleotide in exon 30 of the MYBPC3 gene. The normal sequence with the base that is deleted in braces is: AGAC{C}ATGG. This mutation is denoted c.3327delC at the cDNA level or p.Met1110TrpfsX79 at the protein level. The c.3327delC mutation in the MYBPC3 gene causes a shift in reading frame at codon Methionine 1110, changing it to a Tryptophan, and creates a premature Stop codon at position 79 of the new reading frame. Although this mutation has not been reported previously to our knowledge, it is expected to result in an abnormal, truncated protein or in absence of protein from this allele due to mRNA decay, and therefore is interpreted to be a disease-causing mutation.The variant is found in HCM panel(s). -

not provided Pathogenic:1

May 18, 2016

Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hypertrophic cardiomyopathy 4 Pathogenic:1

Mar 31, 2022

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with hypertrophic cardiomyopathy 4 (HCM; MIM#115197). (I) 0108 - This gene is associated with both recessive and dominant disease. Dominant inheritance is frequently reported in adult onset conditions, however recessive inheritance results in a more severe early onset phenotype (OMIM). (I) 0115 - Variants in this gene are known to have variable expressivity (PMID: 32841044). (I) 0201 - Variant is predicted to cause nonsense-mediated decay (NMD) and loss of protein (premature termination codon is located at least 54 nucleotides upstream of the final exon-exon junction). (SP) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0701 - Other NMD-predicted variants comparable to the one identified in this case have very strong previous evidence for pathogenicity (DECIPHER). (SP) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. This variant has been classified as pathogenic, and observed in individuals with hypertrophic cardiomyopathy (PMID: 32268277, PMID: 28771489, ClinVar). (SP) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

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: rs730880719; hg19: chr11-47354747;