rs397516002

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM1PP3_Moderate

The NM_000256.3(MYBPC3):​c.3083C>T​(p.Thr1028Ile) variant causes a missense change. The variant allele was found at a frequency of 0.00000683 in 1,611,020 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. T1028S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

MYBPC3
NM_000256.3 missense

Scores

8
10
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:7

Conservation

PhyloP100: 5.34

Publications

6 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 18 uncertain in NM_000256.3
PP3
MetaRNN computational evidence supports a deleterious effect, 0.884

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYBPC3NM_000256.3 linkc.3083C>T p.Thr1028Ile missense_variant Exon 29 of 35 ENST00000545968.6 NP_000247.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYBPC3ENST00000545968.6 linkc.3083C>T p.Thr1028Ile missense_variant Exon 29 of 35 5 NM_000256.3 ENSP00000442795.1
MYBPC3ENST00000399249.6 linkc.3083C>T p.Thr1028Ile missense_variant Exon 28 of 34 5 ENSP00000382193.2

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152254
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000405
AC:
1
AN:
247100
AF XY:
0.00000745
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000166
GnomAD4 exome
AF:
0.00000480
AC:
7
AN:
1458766
Hom.:
0
Cov.:
32
AF XY:
0.00000827
AC XY:
6
AN XY:
725846
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44712
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26122
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50582
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1111800
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60348
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152254
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74378
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41472
American (AMR)
AF:
0.00
AC:
0
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68040
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.413
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000315
Hom.:
0
Bravo
AF:
0.0000340

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:7
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Cardiovascular phenotype Pathogenic:1Uncertain:1
Sep 19, 2024
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PS4, PM2, PP3 -

Apr 18, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.T1028I variant (also known as c.3083C>T), located in coding exon 29 of the MYBPC3 gene, results from a C to T substitution at nucleotide position 3083. The threonine at codon 1028 is replaced by isoleucine, an amino acid with similar properties. This variant was observed in individuals reported to have hypertrophic cardiomyopathy (HCM); however, clinical details were limited (Kapplinger JD et al. J Cardiovasc Transl Res, 2014 Apr;7:347-61; Murphy SL et al. J Cardiovasc Transl Res, 2016 Apr;9:153-61). This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Cardiomyopathy Uncertain:2
Mar 02, 2022
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 23, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces threonine with isoleucine at codon 1028 of the MYBPC3 protein. Computational prediction tools indicate that this variant has a deleterious impact on protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in individuals affected with hypertrophic cardiomyopathy (PMID: 26914223, 33495596, 33495597) as well as individuals suspected to be affected with hypertrophic cardiomyopathy (PMID: 24510615). This variant has been identified in 1/247100 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

not provided Uncertain:2
Apr 05, 2019
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.Thr1028Ile variant in MYBPC3 has been identified in 4 individuals with HCM (Kapplinger 2014, LMM unpublished data) and was absent from large population studies. Computational prediction tools and conservation analysis suggest that this variant may impact the protein, though this information is not predictive enough to determine pathogenicity. In summary, the clinical significance of the Thr1028Ile variant is uncertain. The ACMG/AMP Criteria applied: PS4_Mod; PM2; PP3 (2 moderate, 1 supporting) -

May 24, 2022
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Reported in patients referred for HCM genetic testing in the published literature (Kapplinger et al., 2014); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 24510615, 26914223, 18403758) -

Hypertrophic cardiomyopathy Uncertain:2
Dec 19, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 1028 of the MYBPC3 protein (p.Thr1028Ile). This variant is present in population databases (rs397516002, gnomAD no frequency). This missense change has been observed in individuals with hypertrophic cardiomyopathy and/or referred for HCM genetic testing (PMID: 24510615, 26914223; internal data). ClinVar contains an entry for this variant (Variation ID: 164050). 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. -

Mar 25, 2024
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces threonine with isoleucine at codon 1028 of the MYBPC3 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in individuals affected with hypertrophic cardiomyopathy (PMID: 26914223, 33495596, 33495597) as well as individuals with suspected hypertrophic cardiomyopathy (PMID: 24510615). This variant has been identified in 1/247100 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
CardioboostCm
Uncertain
0.33
BayesDel_addAF
Pathogenic
0.17
D
BayesDel_noAF
Uncertain
0.010
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.75
D;T;T
Eigen
Uncertain
0.65
Eigen_PC
Uncertain
0.56
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.97
D;D;D
M_CAP
Pathogenic
0.34
D
MetaRNN
Pathogenic
0.88
D;D;D
MetaSVM
Benign
-0.54
T
MutationAssessor
Uncertain
2.9
M;.;.
PhyloP100
5.3
PrimateAI
Uncertain
0.68
T
PROVEAN
Pathogenic
-4.4
D;.;D
REVEL
Pathogenic
0.67
Sift
Uncertain
0.0030
D;.;D
Sift4G
Pathogenic
0.0010
D;D;D
Vest4
0.94
MVP
0.89
MPC
0.82
ClinPred
0.96
D
GERP RS
4.0
Varity_R
0.41
gMVP
0.84
Mutation Taster
=5/95
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs397516002; hg19: chr11-47355215; API