rs876658028

Variant names:

• chr1-201363323-C-A
• rs876658028
• NM_001276345.2:c.573G>T

Your query was ambiguous. Multiple possible variants found:

• chr1-201363323-C-A
• chr1-201363323-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_001276345.2(TNNT2):​c.573G>T​(p.Met191Ile) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M191T) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TNNT2 NM_001276345.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.20

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]

ENSG00000286600 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 14 uncertain in NM_001276345.2
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.77

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TNNT2	NM_001276345.2	c.573G>T	p.Met191Ile	missense_variant	Exon 12 of 17	ENST00000656932.1	NP_001263274.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TNNT2	ENST00000656932.1	c.573G>T	p.Met191Ile	missense_variant	Exon 12 of 17		NM_001276345.2	ENSP00000499593.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Feb 16, 2015

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant classified as Uncertain Significance - Favor Pathogenic. The p.Met181Ile variant in TNNT2 has not been previously reported in individuals with cardiomyo pathy and was absent from large population studies. This variant was predicted t o be pathogenic using a computational tool clinically validated by our laborator y. This tool's pathogenic prediction is estimated to be correct 94% of the time (Jordan 2011). In summary, while there is some suspicion for a pathogenic role, the clinical significance of the p.Met181Ile variant is uncertain. -

Dilated cardiomyopathy 1D;C1861864:Hypertrophic cardiomyopathy 2;C2676271:Cardiomyopathy, familial restrictive, 3 Uncertain:1

May 22, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 181 of the TNNT2 protein (p.Met181Ile). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TNNT2-related conditions. ClinVar contains an entry for this variant (Variation ID: 229337). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.92
CardioboostCm	Pathogenic	0.93
BayesDel_addAF	Uncertain	0.14	D
BayesDel_noAF	Uncertain	-0.040
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.88	.;.;.;.;D;.;.;.;.;.;D
Eigen	Pathogenic	0.69
Eigen_PC	Uncertain	0.63
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.92	.;D;D;D;D;D;D;.;.;D;.
M_CAP	Pathogenic	0.46	D
MetaRNN	Pathogenic	0.77	D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.66	D
MutationAssessor	Uncertain	2.2	.;.;.;.;M;.;.;.;.;.;.
PrimateAI	Pathogenic	0.81	D
PROVEAN	Uncertain	-2.9	D;D;.;.;.;.;.;.;D;D;D
REVEL	Uncertain	0.61
Sift	Uncertain	0.0010	D;D;.;.;.;.;.;.;D;D;D
Sift4G	Benign	0.079	T;T;D;T;D;T;T;T;T;T;.
Polyphen		1.0, 0.97	.;.;.;.;D;.;.;.;.;.;D
Vest4		0.74
MutPred		0.45		.;.;.;.;Gain of methylation at K186 (P = 0.1636);.;.;.;.;.;.;
MVP		0.93
MPC		1.5
ClinPred		0.98	D
GERP RS		4.9
Varity_R		0.37
gMVP		0.67

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

LitVar

Other links and lift over

dbSNP: rs876658028; hg19: chr1-201332451;