rs397516450

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM1BP4

The NM_001276345.2(TNNT2):​c.248A>G​(p.Asn83Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000991 in 1,613,876 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N83H) has been classified as Uncertain significance.

Frequency

Genomes: š‘“ 0.000039 ( 0 hom., cov: 32)
Exomes š‘“: 0.0000068 ( 0 hom. )

Consequence

TNNT2
NM_001276345.2 missense

Scores

2
9
9

Clinical Significance

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

Conservation

PhyloP100: 1.98

Publications

4 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 1 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 24 uncertain in NM_001276345.2
BP4
Computational evidence support a benign effect (MetaRNN=0.34940726).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TNNT2NM_001276345.2 linkc.248A>G p.Asn83Ser missense_variant Exon 9 of 17 ENST00000656932.1 NP_001263274.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TNNT2ENST00000656932.1 linkc.248A>G p.Asn83Ser missense_variant Exon 9 of 17 NM_001276345.2 ENSP00000499593.1

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152176
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:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000239
AC:
6
AN:
250952
AF XY:
0.0000295
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000440
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000684
AC:
10
AN:
1461700
Hom.:
0
Cov.:
31
AF XY:
0.00000825
AC XY:
6
AN XY:
727114
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44696
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86172
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000809
AC:
9
AN:
1111946
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.435
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:
0.0000394
AC:
6
AN:
152176
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74328
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41448
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.483
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:
0.00
Hom.:
0
Bravo
AF:
0.0000264
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

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

Submissions by phenotype

Dilated cardiomyopathy 1D;C1861864:Hypertrophic cardiomyopathy 2;C2676271:Cardiomyopathy, familial restrictive, 3 Uncertain:3
Jun 12, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Center for Genomics, Ann and Robert H. Lurie Children's Hospital of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

TNNT2 NM_001001430.2 exon 8 p.Asn73Ser (c.218A>G): This variant has been reported in the literature in at least 1 individual with dilated cardiomyopathy (DCM) (Lakdawala 2012 PMID:22464770). This variant is present in 1/17246 East Asian alleles in the Genome Aggregation Database (http://gnomad.broadinstitute.org/rs397516450). This variant is present in ClinVar (Variation ID:43618). Evolutionary conservation and computational predictive tools suggest that this variant may impact the protein. In summary, data on this variant is insufficient for disease classification. Therefore, the clinical significance of this variant is uncertain. -

Sep 23, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 73 of the TNNT2 protein (p.Asn73Ser). This variant is present in population databases (rs397516450, gnomAD 0.006%). This missense change has been observed in individual(s) with dilated cardiomyopathy (PMID: 22464770, 31737537). ClinVar contains an entry for this variant (Variation ID: 43618). 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 expected to disrupt TNNT2 protein function with a positive predictive value of 95%. 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. -

Cardiomyopathy Uncertain:2
Sep 23, 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 asparagine with serine at codon 73 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 at least 2 individuals affected with dilated cardiomyopathy (PMID: 22464770, 31737537). This variant has been identified in 6/250952 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. -

Apr 27, 2023
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces asparagine with serine at codon 73 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 individuals affected with dilated cardiomyopathy (PMID: 22464770, 31737537). This variant has been identified in 6/250952 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 Pathogenic:1
Jun 29, 2017
Institute of Human Genetics, University of Leipzig Medical Center
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Oct 05, 2017
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Needs reassessment: Evidence points to VUS -

Cardiovascular phenotype Uncertain:1
Sep 17, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.N73S variant (also known as c.218A>G), located in coding exon 7 of the TNNT2 gene, results from an A to G substitution at nucleotide position 218. The asparagine at codon 73 is replaced by serine, an amino acid with highly similar properties. This variant was detected in one individual from a dilated cardiomyopathy cohort; however, clinical details were limited (Lakdawala NK et al. J. Card. Fail., 2012 Apr;18:296-303). This variant has also been reported in an exome cohort (Kurzlechner LM et al. J Pers Med, 2022 Apr;12:). This amino acid position is 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
0.079
CardioboostCm
Benign
0.028
BayesDel_addAF
Benign
-0.033
T
BayesDel_noAF
Benign
-0.12
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.51
.;.;.;.;D;.;.;.;.;.;T;.;.;T
Eigen
Uncertain
0.21
Eigen_PC
Uncertain
0.27
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.88
.;D;D;D;D;D;D;.;.;D;.;.;D;.
M_CAP
Pathogenic
0.48
D
MetaRNN
Benign
0.35
T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.6
.;.;.;.;M;.;.;.;.;.;.;.;.;.
PhyloP100
2.0
PrimateAI
Uncertain
0.53
T
PROVEAN
Benign
-1.6
N;N;.;.;.;.;.;.;N;N;N;N;N;N
REVEL
Uncertain
0.44
Sift
Benign
0.18
T;T;.;.;.;.;.;.;D;T;T;T;T;D
Sift4G
Benign
0.51
T;T;T;T;T;T;T;T;T;T;.;T;T;.
Polyphen
0.92, 0.74
.;.;.;.;P;.;.;.;.;.;P;.;.;.
Vest4
0.44
MutPred
0.10
.;.;.;.;Gain of phosphorylation at N83 (P = 0.0102);.;.;.;.;.;.;Gain of phosphorylation at N83 (P = 0.0102);.;.;
MVP
0.95
MPC
1.0
ClinPred
0.19
T
GERP RS
4.7
Varity_R
0.14
gMVP
0.64
Mutation Taster
=0/100
disease causing (ClinVar)

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: rs397516450; hg19: chr1-201334784; API