11-47337756-C-T

Position:

• chr11-47337756-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PM2

The NM_000256.3(MYBPC3):​c.2347G>A​(p.Val783Met) variant causes a missense 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 Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: MYBPC3 NM_000256.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.14

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 Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a domain Fibronectin type-III 1 (size 96) in uniprot entity MYPC3_HUMAN there are 31 pathogenic changes around while only 3 benign (91%) in NM_000256.3
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MYBPC3	NM_000256.3	c.2347G>A	p.Val783Met	missense_variant	24/35	ENST00000545968.6	NP_000247.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MYBPC3	ENST00000545968.6	c.2347G>A	p.Val783Met	missense_variant	24/35	5	NM_000256.3	ENSP00000442795.1
MYBPC3	ENST00000399249.6	c.2347G>A	p.Val783Met	missense_variant	23/34	5		ENSP00000382193.2
MYBPC3	ENST00000544791.1	n.2347G>A		non_coding_transcript_exon_variant	24/27	5		ENSP00000444259.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1403440 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 692772

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Oct 24, 2017

A variant of uncertain significance has been identified in the MYBPC3 gene. The V783M variant has not been published as pathogenic or been reported as benign to our knowledge. This variant is not observed in large population cohorts (Lek et al., 2016). However, the V783M variant is a conservative amino acid substitution, which is not likely to impact secondary protein structure as these residues share similar properties. This substitution occurs at a position where amino acids with similar properties to valine (V) are tolerated across species. Finally, in silico analysis is inconsistent in its predictions as to whether or not the variant is damaging to the protein structure/function. -

Hypertrophic cardiomyopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 17, 2023

Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. ClinVar contains an entry for this variant (Variation ID: 452909). This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 783 of the MYBPC3 protein (p.Val783Met). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with MYBPC3-related conditions. -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 09, 2022

The p.V783M variant (also known as c.2347G>A), located in coding exon 24 of the MYBPC3 gene, results from a G to A substitution at nucleotide position 2347. The valine at codon 783 is replaced by methionine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.49
CardioboostCm	Pathogenic	0.91
BayesDel_addAF	Uncertain	0.035	T
BayesDel_noAF	Benign	-0.19
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.25	T;T;T
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.96	D;D;D
M_CAP	Pathogenic	0.33	D
MetaRNN	Uncertain	0.65	D;D;D
MetaSVM	Uncertain	-0.14	T
MutationAssessor	Pathogenic	3.0	M;.;.
PrimateAI	Benign	0.44	T
PROVEAN	Uncertain	-2.5	N;.;N
REVEL	Uncertain	0.41
Sift	Uncertain	0.0010	D;.;D
Sift4G	Pathogenic	0.0010	D;D;D
Vest4		0.58
MVP		0.90
MPC		0.80
ClinPred		0.95	D
GERP RS		4.7
Varity_R		0.38
gMVP		0.54

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: rs1060499878; hg19: chr11-47359307;