rs727504322

chr1-201365191-G-A

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 0P and 7B. BP4_Moderate BP7 BS2

The NM_001276345.2(TNNT2):c.411C>T(p.Ile137=) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000143 in 1,611,086 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000014 (0 hom.)
• Consequence: TNNT2 NM_001276345.2 splice_region, synonymous
• Scores: Splicing: ADA: 0.006673
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5 B:1
• Conservation: PhyloP100: -0.519

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]

ACMG classification

Verdict is Benign. Variant got -7 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.26).
• BP7: Synonymous conserved (PhyloP=-0.519 with no splicing effect.
• BS2: High AC in GnomAdExome at 9 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TNNT2	NM_001276345.2	c.411C>T	p.Ile137=	splice_region_variant, synonymous_variant	10/17	ENST00000656932.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TNNT2	ENST00000656932.1	c.411C>T	p.Ile137=	splice_region_variant, synonymous_variant	10/17		NM_001276345.2	A2

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152170 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000193

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000358 AC: 9 AN: 251490 Hom.: 0 AF XY: 0.0000441 AC XY: 6 AN XY: 135922

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000116

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000653

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000264

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000144 AC: 21 AN: 1458916 Hom.: 0 Cov.: 29 AF XY: 0.0000193 AC XY: 14 AN XY: 726002

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.000134

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000348

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000992

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152170 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74324

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000655

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000193

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000688 Hom.: 0

Bravo AF: 0.0000151

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:5 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Cardiomyopathy Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jun 08, 2023	This synonymous variant causes a nucleotide substitution but does not change the encoded amino acid at codon 127 of the TNNT2 protein. Splice site prediction tools and conservation analysis are inconclusive regarding the impact of this variant on RNA splicing. To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with TNNT2-related disorders in the literature. This variant has been identified in 9/251490 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Feb 05, 2024	This synonymous variant causes a nucleotide substitution but does not change the encoded amino acid at codon 127 of the TNNT2 protein. Splice site prediction tools and conservation analysis are inconclusive regarding the impact of this variant on RNA splicing. To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with TNNT2-related disorders in the literature. This variant has been identified in 9/251490 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

Uncertain significance, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Apr 15, 2022	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Jan 04, 2024	This sequence change affects codon 127 of the TNNT2 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the TNNT2 protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs727504322, gnomAD 0.01%). 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: 177785). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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. -

not specified Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Mar 01, 2008

proposed classification - variant undergoing re-assessment, contact laboratory -

Cardiovascular phenotype Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 08, 2022

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.26
Cadd	Benign	6.9
Dann	Benign	0.80

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.0067
dbscSNV1_RF	Benign	0.15
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: rs727504322; hg19: chr1-201334319; COSMIC: COSV52660783; COSMIC: COSV52660783;