NM_000256.3:c.436A>C

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_000256.3(MYBPC3):​c.436A>C​(p.Thr146Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000244 in 1,559,412 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 17/23 in silico tools predict a benign 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. T146I) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000026 ( 1 hom. )

Consequence

MYBPC3
NM_000256.3 missense

Scores

1
19

Clinical Significance

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

Conservation

PhyloP100: -0.424

Publications

4 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: Likely_benign. The variant received -4 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.055594742).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYBPC3NM_000256.3 linkc.436A>C p.Thr146Pro missense_variant Exon 4 of 35 ENST00000545968.6 NP_000247.2 Q14896-1A5YM48

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYBPC3ENST00000545968.6 linkc.436A>C p.Thr146Pro missense_variant Exon 4 of 35 5 NM_000256.3 ENSP00000442795.1 Q14896-1
MYBPC3ENST00000399249.6 linkc.436A>C p.Thr146Pro missense_variant Exon 4 of 34 5 ENSP00000382193.2 A8MXZ9
MYBPC3ENST00000544791.1 linkn.436A>C non_coding_transcript_exon_variant Exon 4 of 27 5 ENSP00000444259.1 F5GZR4

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
151692
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000179
AC:
3
AN:
167140
AF XY:
0.0000225
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:
0.0000149
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000256
AC:
36
AN:
1407720
Hom.:
1
Cov.:
35
AF XY:
0.0000316
AC XY:
22
AN XY:
695332
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
31992
American (AMR)
AF:
0.00
AC:
0
AN:
36860
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25276
East Asian (EAS)
AF:
0.00
AC:
0
AN:
36446
South Asian (SAS)
AF:
0.000100
AC:
8
AN:
79746
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
49804
Middle Eastern (MID)
AF:
0.000538
AC:
3
AN:
5578
European-Non Finnish (NFE)
AF:
0.0000221
AC:
24
AN:
1083694
Other (OTH)
AF:
0.0000171
AC:
1
AN:
58324
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.504
Heterozygous variant carriers
0
3
5
8
10
13
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:
0.0000132
AC:
2
AN:
151692
Hom.:
0
Cov.:
33
AF XY:
0.0000270
AC XY:
2
AN XY:
74080
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41244
American (AMR)
AF:
0.00
AC:
0
AN:
15234
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5146
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10516
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
67954
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.550
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.0000579
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.0000262
AC:
3

ClinVar

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

Submissions by phenotype

Hypertrophic cardiomyopathy Uncertain:2
Oct 17, 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 proline, which is neutral and non-polar, at codon 146 of the MYBPC3 protein (p.Thr146Pro). This variant is present in population databases (rs397516048, gnomAD 0.009%). This missense change has been observed in individual(s) with hypertrophic cardiomyopathy (PMID: 27532257). ClinVar contains an entry for this variant (Variation ID: 42750). 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 tolerated. 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. -

Sep 16, 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 proline at codon 146 of the MYBPC3 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in one individual affected with hypertrophic cardiomyopathy (PMID: 27532257). This variant has been identified in 3/193038 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. -

Cardiovascular phenotype Uncertain:1Benign:1
Apr 08, 2025
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PM2, BS4, BP4 -

Apr 16, 2025
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

not specified Uncertain:1
May 02, 2018
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.Thr146Pro variant in MYBPC3 has been identified by our laboratory in 1 adu lt with DCM and PVCs and in 2 adults with HCM, one of whom carried a likely path ogenic variant in another gene. This variant has also been identified in 3/19303 8 chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadins titute.org; dbSNP rs397516048). Computational prediction tools and conservation analysis suggest that the p.Thr146Pro variant may not impact the protein, though this information is not predictive enough to rule out pathogenicity. In summary , the clinical significance of the p.Thr146Pro variant is uncertain. ACMG/AMP Cr iteria applied: PM2; BP4. -

Cardiomyopathy Uncertain:1
Jul 11, 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 proline at codon 146 of the MYBPC3 protein. Computational prediction tools indicate that this variant has a neutral impact on protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with hypertrophic cardiomyopathy (PMID: 27532257). This variant has been identified in 3/193038 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. -

Hypertrophic cardiomyopathy 4 Uncertain:1
Feb 14, 2022
MGZ Medical Genetics Center
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Primary familial hypertrophic cardiomyopathy Uncertain:1
Nov 11, 2014
Blueprint Genetics
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
CardioboostCm
Benign
0.0053
BayesDel_addAF
Benign
-0.31
T
BayesDel_noAF
Benign
-0.49
CADD
Benign
0.46
DANN
Benign
0.55
DEOGEN2
Benign
0.097
T;T;T
Eigen
Benign
-1.4
Eigen_PC
Benign
-1.5
FATHMM_MKL
Benign
0.0072
N
LIST_S2
Benign
0.24
T;T;T
M_CAP
Benign
0.0084
T
MetaRNN
Benign
0.056
T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
0.0
N;.;.
PhyloP100
-0.42
PrimateAI
Uncertain
0.50
T
PROVEAN
Benign
0.55
N;N;N
REVEL
Benign
0.057
Sift
Benign
0.34
T;T;T
Sift4G
Benign
0.28
T;T;T
Polyphen
0.0
B;.;.
Vest4
0.17
MVP
0.38
MPC
0.28
ClinPred
0.10
T
GERP RS
-1.1
Varity_R
0.082
gMVP
0.15
Mutation Taster
=88/12
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

Publications

Other links and lift over

dbSNP: rs397516048; hg19: chr11-47371634; API