rs397516001

chr11-47333678-G-GT

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_000256.3(MYBPC3):c.3068_3069insA(p.Asn1023LysfsTer28) 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: 33)
• Consequence: MYBPC3 NM_000256.3 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 3.11

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 12 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 11-47333678-G-GT is Pathogenic according to our data. Variant chr11-47333678-G-GT is described in ClinVar as [Pathogenic]. Clinvar id is 42683.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYBPC3	NM_000256.3	c.3068_3069insA	p.Asn1023LysfsTer28	frameshift_variant	29/35	ENST00000545968.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYBPC3	ENST00000545968.6	c.3068_3069insA	p.Asn1023LysfsTer28	frameshift_variant	29/35	5	NM_000256.3	P4
MYBPC3	ENST00000399249.6	c.3068_3069insA	p.Asn1023LysfsTer28	frameshift_variant	28/34	5		A2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hypertrophic cardiomyopathy Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Feb 17, 2011

The Asn1023fs variant has been reported in one individual with a clinical diagno sis of HCM (Brito 2005) where the variant was described as de novo. In addition , this variant is predicted to cause a frameshift, which alters the protein's am ino acid sequence beginning at codon 1023 and leads to a premature stop codon 28 amino acids downstream. This alteration is then predicted to lead to a truncat ed or absent protein. Loss of function is an established mechanism of disease f or the MYBPC3 gene, which makes it highly likely that the Asn1023fs variant is p athogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.22		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.22		Position offset: 15

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs397516001; hg19: chr11-47355229;