rs727504259

Variant names:

• chr11-47332140-C-A
• rs727504259
• NM_000256.3:c.3746G>T

Your query was ambiguous. Multiple possible variants found:

• chr11-47332140-C-A
• chr11-47332140-C-T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_000256.3(MYBPC3):​c.3746G>T​(p.Gly1249Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,360 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G1249D) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MYBPC3 NM_000256.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:5
• Conservation: PhyloP100: 7.56
• Publications: 3 publications found

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]

MYBPC3 Gene-Disease associations (from GenCC):

• hypertrophic cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• hypertrophic cardiomyopathy 4

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
• left ventricular noncompaction 10

  Inheritance: AR, AD Classification: DEFINITIVE, MODERATE, LIMITED Submitted by: Ambry Genetics
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• atrial fibrillation

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• dilated cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 25 uncertain in NM_000256.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.988

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYBPC3	NM_000256.3	c.3746G>T	p.Gly1249Val	missense_variant	Exon 33 of 35	ENST00000545968.6	NP_000247.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYBPC3	ENST00000545968.6	c.3746G>T	p.Gly1249Val	missense_variant	Exon 33 of 35	5	NM_000256.3	ENSP00000442795.1
MYBPC3	ENST00000399249.6	c.3746G>T	p.Gly1249Val	missense_variant	Exon 32 of 34	5		ENSP00000382193.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461360 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 726972

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53074

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111858

Other (OTH) AF: 0.00 AC: 0 AN: 60364

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:5

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Pathogenic:1 Uncertain:1

Jul 25, 2018

Blueprint Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jan 17, 2017

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

A variant of uncertain significance has been identified in the MYBPC3 gene. The G1249V variant has been published in association with HCM (Berge et al., 2014); however, familial segregation information, in vitro functional studies and additional clinical information were not included. The G1249V variant was not observed in approximately 6,100 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. This substitution occurs at a position that is conserved across species and in silico analysis predicts this variant is probably damaging to the protein structure/function. Nevertheless, the G1249V variant is a conservative amino acid substitution, which is not likely to impact secondary protein structure as these residues share similar properties. -

Hypertrophic cardiomyopathy Uncertain:2

Aug 15, 2023

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Apr 06, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 1249 of the MYBPC3 protein (p.Gly1249Val). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with hypertrophic cardiomyopathy (PMID: 24111713, 27532257, 33673806). ClinVar contains an entry for this variant (Variation ID: 177653). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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. -

not specified Uncertain:1

Sep 12, 2016

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Gly1249Val variant in MYBPC3 has been reported in 4 individuals with HCM ( Berge 2014, LMM data) and was absent from large population studies. Computationa l prediction tools and conservation analysis suggest that the p.Gly1249Val varia nt may impact the protein, though this information is not predictive enough to d etermine pathogenicity. In summary, the clinical significance of the p.Gly1249Va l variant is uncertain. -

Cardiovascular phenotype Uncertain:1

Jul 03, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.G1249V variant (also known as c.3746G>T), located in coding exon 33 of the MYBPC3 gene, results from a G to T substitution at nucleotide position 3746. The glycine at codon 1249 is replaced by valine, an amino acid with dissimilar properties. This alteration has been reported in individuals with hypertrophic cardiomyopathy (HCM) (Bos JM et al. Mayo Clin Proc, 2014 Jun;89:727-37; Berge KE et al. Clin Genet, 2014 Oct;86:355-60; Alfares AA et al. Genet Med, 2015 Nov;17:880-8; Dejgaard LA et al. Data Brief, 2017 Dec;15:30-39; Walsh R et al. Genet Med, 2017 Feb;19:192-203). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.92
CardioboostCm	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.44
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.89	D;T;T
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D;D
M_CAP	Pathogenic	0.73	D
MetaRNN	Pathogenic	0.99	D;D;D
MetaSVM	Pathogenic	0.95	D
MutationAssessor	Pathogenic	4.6	H;.;.
PhyloP100		7.6
PrimateAI	Uncertain	0.63	T
PROVEAN	Pathogenic	-7.9	D;.;D
REVEL	Pathogenic	0.92
Sift	Uncertain	0.0010	D;.;D
Sift4G	Pathogenic	0.0010	D;D;D
Vest4		0.99
MVP		0.99
MPC		0.93
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.96
gMVP		0.97
Mutation Taster		=1/99	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.080		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs727504259; hg19: chr11-47353691;