rs1555123744

Variant names:

• chr11-47351311-C-T
• rs1555123744
• NM_000256.3:c.220G>A

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM1 PM2

The NM_000256.3(MYBPC3):​c.220G>A​(p.Ala74Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000007 in 1,428,328 control chromosomes in the GnomAD database, with no homozygous occurrence. 15/23 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A74A) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.0e-7 (0 hom.)
• Consequence: MYBPC3 NM_000256.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 3.02
• 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: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• left ventricular noncompaction 10

  Inheritance: AD, AR 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
• congenital heart disease

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• dilated cardiomyopathy

  Inheritance: AR, AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 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, 24 uncertain in NM_000256.3
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000256.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYBPC3	NM_000256.3	MANE Select	c.220G>A	p.Ala74Thr	missense	Exon 2 of 35	NP_000247.2	Q14896-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYBPC3	ENST00000545968.6	TSL:5 MANE Select	c.220G>A	p.Ala74Thr	missense	Exon 2 of 35	ENSP00000442795.1	Q14896-1
	MYBPC3	ENST00000399249.6	TSL:5	c.220G>A	p.Ala74Thr	missense	Exon 2 of 34	ENSP00000382193.2	A8MXZ9
	MYBPC3	ENST00000544791.1	TSL:5	n.220G>A		non_coding_transcript_exon	Exon 2 of 27	ENSP00000444259.1	F5GZR4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 7.00e-7 AC: 1 AN: 1428328 Hom.: 0 Cov.: 35 AF XY: 0.00 AC XY: 0 AN XY: 707190

African (AFR) AF: 0.00 AC: 0 AN: 32556

American (AMR) AF: 0.00 AC: 0 AN: 40046

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25500

East Asian (EAS) AF: 0.00 AC: 0 AN: 37564

South Asian (SAS) AF: 0.00 AC: 0 AN: 81876

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50970

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5720

European-Non Finnish (NFE) AF: 9.13e-7 AC: 1 AN: 1094962

Other (OTH) AF: 0.00 AC: 0 AN: 59134

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	2	-	Hypertrophic cardiomyopathy (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
CardioboostCm	Benign	0.00071
BayesDel_addAF	Benign	-0.24	T
BayesDel_noAF	Benign	-0.59
CADD	Benign	18
DANN	Uncertain	0.99
DEOGEN2	Benign	0.14	T
Eigen	Benign	-0.53
Eigen_PC	Benign	-0.55
FATHMM_MKL	Benign	0.76	D
LIST_S2	Benign	0.62	T
M_CAP	Benign	0.040	D
MetaRNN	Uncertain	0.49	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.89	L
PhyloP100		3.0
PrimateAI	Benign	0.33	T
PROVEAN	Benign	-0.13	N
REVEL	Benign	0.050
Sift	Benign	0.087	T
Sift4G	Benign	0.076	T
Polyphen		0.32	B
Vest4		0.069
MutPred		0.28		Gain of glycosylation at A74 (P = 0.0475)
MVP		0.68
MPC		0.22
ClinPred		0.52	D
GERP RS		2.4
Varity_R		0.10
gMVP		0.17
Mutation Taster		=92/8	polymorphism

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

Other links and lift over

dbSNP: rs1555123744; hg19: chr11-47372862;