rs1553284388

Positions:

• chr1-201368209-TC-T

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_001276345.2(TNNT2):​c.115delG​(p.Glu39fs) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TNNT2 NM_001276345.2 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.14

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 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TNNT2	NM_001276345.2	c.115delG	p.Glu39fs	frameshift_variant	6/17	ENST00000656932.1	NP_001263274.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TNNT2	ENST00000656932.1	c.115delG	p.Glu39fs	frameshift_variant	6/17		NM_001276345.2	ENSP00000499593.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Dilated cardiomyopathy 1D Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Center of Genomic medicine, Geneva, University Hospital of Geneva

Nov 21, 2016

This TNNT2 variant was found in compound heterozygosity with one another TNNT2 variant in a young patient with severe dilated cardiomyopathy. The patient also harbours a pathogenic variant in TTN gene. The combination of these three variants explains this severe phenotype in a such young patient. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs1553284388; hg19: chr1-201337337;