rs977277400

Variant names:

• chr11-47336012-C-A
• rs977277400
• NM_000256.3:c.2603-1G>T

Your query was ambiguous. Multiple possible variants found:

• chr11-47336012-C-A
• chr11-47336012-C-G
• chr11-47336012-C-T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_000256.3(MYBPC3):​c.2603-1G>T variant causes a splice acceptor, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: MYBPC3 NM_000256.3 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 5.24
• Publications: 0 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 6 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.03529412 fraction of the gene. Cryptic splice site detected, with MaxEntScore 9.7, offset of 10, new splice context is: ctctgcccatgtccccccAGcga. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-47336012-C-A is Pathogenic according to our data. Variant chr11-47336012-C-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 2125400.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYBPC3	NM_000256.3	c.2603-1G>T		splice_acceptor_variant, intron_variant	Intron 25 of 34	ENST00000545968.6	NP_000247.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYBPC3	ENST00000545968.6	c.2603-1G>T		splice_acceptor_variant, intron_variant	Intron 25 of 34	5	NM_000256.3	ENSP00000442795.1
MYBPC3	ENST00000399249.6	c.2603-1G>T		splice_acceptor_variant, intron_variant	Intron 24 of 33	5		ENSP00000382193.2
MYBPC3	ENST00000544791.1	n.*108-1G>T		splice_acceptor_variant, intron_variant	Intron 25 of 26	5		ENSP00000444259.1

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1364986 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 669800

African (AFR) AF: 0.00 AC: 0 AN: 30208

American (AMR) AF: 0.00 AC: 0 AN: 34490

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 21348

East Asian (EAS) AF: 0.00 AC: 0 AN: 36158

South Asian (SAS) AF: 0.00 AC: 0 AN: 70414

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50148

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 3796

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1062258

Other (OTH) AF: 0.00 AC: 0 AN: 56166

GnomAD4 genome Cov.: 30

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hypertrophic cardiomyopathy Pathogenic:1

Oct 02, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects an acceptor splice site in intron 25 of the MYBPC3 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in MYBPC3 are known to be pathogenic (PMID: 19574547). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individual(s) with hypertrophic cardiomyopathy (PMID: 25351510, 27532257, 30297972). ClinVar contains an entry for this variant (Variation ID: 2125400). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.35
CADD	Pathogenic	35
DANN	Uncertain	0.99
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.98	D
PhyloP100		5.2
GERP RS		5.3
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.99		Position offset: -11
DS_AL_spliceai		1.0		Position offset: -1

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

Other links and lift over

dbSNP: rs977277400; hg19: chr11-47357563; COSMIC: COSV99920035;