1-201362015-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 4P and 1B. PM1PM5BP4

The NM_001276345.2(TNNT2):​c.617G>A​(p.Arg206Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000123 in 1,461,882 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R206W) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

TNNT2
NM_001276345.2 missense

Scores

7
13

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:9

Conservation

PhyloP100: 2.02

Publications

3 publications found
Variant links:
Genes affected
TNNT2 (HGNC:11949): (troponin T2, cardiac type) This gene encodes the cardiac isoform of troponin T. The encoded protein is the tropomyosin-binding subunit of the troponin complex, which is located on the thin filament of striated muscles and regulates muscle contraction in response to alterations in intracellular calcium ion concentration. Mutations in this gene have been associated with familial hypertrophic cardiomyopathy as well as with dilated cardiomyopathy. [provided by RefSeq, May 2022]
TNNT2 Gene-Disease associations (from GenCC):
  • dilated cardiomyopathy
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • dilated cardiomyopathy 1D
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
  • hypertrophic cardiomyopathy
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • hypertrophic cardiomyopathy 2
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • hypertrophic cardiomyopathy 3
    Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
  • cardiomyopathy, familial restrictive, 3
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • familial isolated dilated cardiomyopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • familial isolated restrictive cardiomyopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • left ventricular noncompaction
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • cardiomyopathy
    Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics
  • arrhythmogenic right ventricular cardiomyopathy
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 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, 20 uncertain in NM_001276345.2
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-201362016-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 181625.
BP4
Computational evidence support a benign effect (MetaRNN=0.2767505).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TNNT2NM_001276345.2 linkc.617G>A p.Arg206Gln missense_variant Exon 14 of 17 ENST00000656932.1 NP_001263274.1 P45379-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TNNT2ENST00000656932.1 linkc.617G>A p.Arg206Gln missense_variant Exon 14 of 17 NM_001276345.2 ENSP00000499593.1 P45379-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.00000795
AC:
2
AN:
251486
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000578
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:
0.00
GnomAD4 exome
AF:
0.0000123
AC:
18
AN:
1461882
Hom.:
0
Cov.:
32
AF XY:
0.0000124
AC XY:
9
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.0000671
AC:
3
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000126
AC:
14
AN:
1112006
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.464
Heterozygous variant carriers
0
1
3
4
6
7
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
Cov.:
33
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.00000378
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:9
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cardiomyopathy Uncertain:2
Mar 05, 2024
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jun 20, 2023
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces arginine with glutamine at codon 196 of the TNNT2 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 two individuals affected with dilated cardiomyopathy (PMID: 31514951, 34935411). One of these individuals also carried a pathogenic truncation variant in the TTN gene (PMID: 34935411). This variant has been identified in 3/282874 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. -

Dilated cardiomyopathy 1D;C1861864:Hypertrophic cardiomyopathy 2;C2676271:Cardiomyopathy, familial restrictive, 3 Uncertain:2
Jan 23, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 196 of the TNNT2 protein (p.Arg196Gln). This variant is present in population databases (rs371047521, gnomAD 0.006%). This missense change has been observed in individual(s) with dilated cardiomyopathy (PMID: 31514951). ClinVar contains an entry for this variant (Variation ID: 537255). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt TNNT2 protein function with a negative predictive value of 80%. This variant disrupts the p.Arg196 amino acid residue in TNNT2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 26899768, 31514951). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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. -

Jul 28, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dilated cardiomyopathy 1D Uncertain:1
Apr 11, 2023
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

See cases Uncertain:1
Oct 20, 2023
Institute of Human Genetics, University Hospital Muenster
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

ACMG categories: PM5 -

Cardiomyopathy, familial restrictive, 3 Uncertain:1
Apr 11, 2023
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hypertrophic cardiomyopathy 2 Uncertain:1
Apr 11, 2023
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Uncertain:1
May 08, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R196Q variant (also known as c.587G>A), located in coding exon 12 of the TNNT2 gene, results from a G to A substitution at nucleotide position 587. The arginine at codon 196 is replaced by glutamine, an amino acid with highly similar properties. This variant has been detected in a dilated cardiomyopathy (DCM) cohort; however, details were limited (Gigli M et al. J Am Coll Cardiol. 2019 09;74(11):1480-1490). This amino acid position is not well 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.30
CardioboostCm
Uncertain
0.26
BayesDel_addAF
Benign
-0.0031
T
BayesDel_noAF
Uncertain
-0.070
CADD
Uncertain
24
DANN
Benign
0.81
DEOGEN2
Uncertain
0.46
.;.;.;.;T;.;.;.;.;.;T
Eigen
Benign
-0.42
Eigen_PC
Benign
-0.28
FATHMM_MKL
Benign
0.30
N
LIST_S2
Uncertain
0.93
.;D;D;D;D;D;D;.;.;D;.
M_CAP
Uncertain
0.28
D
MetaRNN
Benign
0.28
T;T;T;T;T;T;T;T;T;T;T
MetaSVM
Benign
-0.29
T
MutationAssessor
Benign
0.0
.;.;.;.;N;.;.;.;.;.;.
PhyloP100
2.0
PrimateAI
Uncertain
0.52
T
PROVEAN
Benign
0.75
N;N;.;.;N;.;.;.;N;N;N
REVEL
Uncertain
0.34
Sift
Benign
1.0
T;T;.;.;D;.;.;.;T;T;T
Sift4G
Benign
0.62
T;T;T;T;T;T;T;T;T;T;.
Polyphen
0.48
.;.;.;.;P;.;.;.;.;.;.
Vest4
0.22
MVP
0.87
MPC
0.99
ClinPred
0.38
T
GERP RS
3.5
Varity_R
0.091
gMVP
0.49
Mutation Taster
=0/100
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.050
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: rs371047521; hg19: chr1-201331143; API