NM_000256.3:c.2063C>A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM1BP4_Moderate

The NM_000256.3(MYBPC3):​c.2063C>A​(p.Thr688Lys) variant causes a missense change. The variant allele was found at a frequency of 0.0000207 in 1,596,766 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

MYBPC3
NM_000256.3 missense

Scores

1
19

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 3.84
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM1
In a domain Ig-like C2-type 5 (size 126) in uniprot entity MYPC3_HUMAN there are 34 pathogenic changes around while only 4 benign (89%) in NM_000256.3
BP4
Computational evidence support a benign effect (MetaRNN=0.087326676).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYBPC3NM_000256.3 linkc.2063C>A p.Thr688Lys missense_variant Exon 21 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.2063C>A p.Thr688Lys missense_variant Exon 21 of 35 5 NM_000256.3 ENSP00000442795.1 Q14896-1
MYBPC3ENST00000399249.6 linkc.2063C>A p.Thr688Lys missense_variant Exon 20 of 34 5 ENSP00000382193.2 A8MXZ9
MYBPC3ENST00000544791.1 linkn.2063C>A non_coding_transcript_exon_variant Exon 21 of 27 5 ENSP00000444259.1 F5GZR4

Frequencies

GnomAD3 genomes
AF:
0.0000328
AC:
5
AN:
152222
Hom.:
0
Cov.:
32
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000441
AC:
1
AN:
226604
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
122966
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000988
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000194
AC:
28
AN:
1444426
Hom.:
0
Cov.:
31
AF XY:
0.0000167
AC XY:
12
AN XY:
716554
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000254
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000328
AC:
5
AN:
152340
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74498
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000735
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000113
ExAC
AF:
0.00000828
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hypertrophic cardiomyopathy Uncertain:2
Dec 14, 2023
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 lysine, which is basic and polar, at codon 688 of the MYBPC3 protein (p.Thr688Lys). This variant is present in population databases (rs3729946, gnomAD 0.002%). This missense change has been observed in individual(s) with clinical features of MYBPC3-related conditions (PMID: 30847666). ClinVar contains an entry for this variant (Variation ID: 180962). 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. -

Dec 18, 2023
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 lysine at codon 688 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 an individual affected with an unspecified cardiomyopathy (PMID: 30847666). This variant has been identified in 2/258004 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;C3715165:Left ventricular noncompaction 10 Uncertain:1
Sep 10, 2021
Fulgent Genetics, Fulgent Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Cardiomyopathy Uncertain:1
Mar 16, 2023
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 lysine at codon 688 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 an individual affected with an unspecified cardiomyopathy (PMID: 30847666). This variant has been identified in 2/258004 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:1
Dec 17, 2019
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Not observed at a significant frequency in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Reported as likely benign in a study of the pathogenic burden in ExAC (Kobayashi et al., 2017); This variant is associated with the following publications: (PMID: 28166811, 30847666) -

Cardiovascular phenotype Uncertain:1
May 17, 2023
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.T688K variant (also known as c.2063C>A), located in coding exon 21 of the MYBPC3 gene, results from a C to A substitution at nucleotide position 2063. The threonine at codon 688 is replaced by lysine, an amino acid with similar properties. This variant was detected in a cardiomyopathy genetic testing cohort; however, clinical details were limited (van Lint FHM et al. Neth Heart J, 2019 Jun;27:304-309). This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.21
CardioboostCm
Benign
0.0032
BayesDel_addAF
Benign
-0.058
T
BayesDel_noAF
Benign
-0.32
CADD
Benign
20
DANN
Benign
0.93
DEOGEN2
Benign
0.11
T;T;T
Eigen
Benign
-0.82
Eigen_PC
Benign
-0.63
FATHMM_MKL
Benign
0.69
D
LIST_S2
Benign
0.64
T;T;T
M_CAP
Benign
0.021
T
MetaRNN
Benign
0.087
T;T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
-0.71
N;.;.
PrimateAI
Uncertain
0.48
T
PROVEAN
Benign
-0.21
N;.;N
REVEL
Benign
0.10
Sift
Benign
0.28
T;.;T
Sift4G
Benign
0.44
T;T;T
Vest4
0.36
MVP
0.62
MPC
0.27
ClinPred
0.29
T
GERP RS
4.0
Varity_R
0.18
gMVP
0.39

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs3729946; hg19: chr11-47361206; API