2-178679958-CTCTTCT-CTCT

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 1P and 0B. PM4_Supporting

The NM_001267550.2(TTN):c.33513_33515delAGA(p.Glu11172del) variant causes a disruptive inframe deletion change. The variant allele was found at a frequency of 0.0000942 in 1,613,002 control chromosomes in the GnomAD database, including 1 homozygotes. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00015 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000088 ( 1 hom. )

Consequence

TTN
NM_001267550.2 disruptive_inframe_deletion

Scores

Not classified

Clinical Significance

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

Conservation

PhyloP100: 3.88

Variant links:

Genes affected

TTN (HGNC:12403): (titin) This gene encodes a large abundant protein of striated muscle. The product of this gene is divided into two regions, a N-terminal I-band and a C-terminal A-band. The I-band, which is the elastic part of the molecule, contains two regions of tandem immunoglobulin domains on either side of a PEVK region that is rich in proline, glutamate, valine and lysine. The A-band, which is thought to act as a protein-ruler, contains a mixture of immunoglobulin and fibronectin repeats, and possesses kinase activity. An N-terminal Z-disc region and a C-terminal M-line region bind to the Z-line and M-line of the sarcomere, respectively, so that a single titin molecule spans half the length of a sarcomere. Titin also contains binding sites for muscle associated proteins so it serves as an adhesion template for the assembly of contractile machinery in muscle cells. It has also been identified as a structural protein for chromosomes. Alternative splicing of this gene results in multiple transcript variants. Considerable variability exists in the I-band, the M-line and the Z-disc regions of titin. Variability in the I-band region contributes to the differences in elasticity of different titin isoforms and, therefore, to the differences in elasticity of different muscle types. Mutations in this gene are associated with familial hypertrophic cardiomyopathy 9, and autoantibodies to titin are produced in patients with the autoimmune disease scleroderma. [provided by RefSeq, Feb 2012]

TTN links:

TTN-AS1 (HGNC:44124): (TTN antisense RNA 1) This gene encodes a non-coding RNA transcribed from the opposite strand to the titin gene. [provided by RefSeq, Aug 2016]

TTN-AS1 links:

LOC124906100 (HGNC:):

LOC124906100 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM4

Nonframeshift variant in NON repetitive region in NM_001267550.2. Strenght limited to Supporting due to length of the change: 1aa.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TTN	NM_001267550.2 link	c.33513_33515delAGA	p.Glu11172del	disruptive_inframe_deletion	Exon 140 of 363	ENST00000589042.5	NP_001254479.2	A0A0A0MTS7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TTN	ENST00000589042.5 link	c.33513_33515delAGA	p.Glu11172del	disruptive_inframe_deletion	Exon 140 of 363	5	NM_001267550.2	ENSP00000467141.1		A0A0A0MTS7

Frequencies

GnomAD3 genomes

AF:

0.000151

AC:

AN:

151904

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000290

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000657

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000386

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00633

Gnomad NFE

AF:

0.0000883

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000125

AC:

AN:

248470

Hom.:

AF XY:

0.000148

AC XY:

AN XY:

134786

show subpopulations

Gnomad AFR exome

AF:

0.000259

Gnomad AMR exome

AF:

0.0000873

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000223

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000169

Gnomad OTH exome

AF:

0.000166

GnomAD4 exome

AF:

0.0000883

AC:

129

AN:

1460980

Hom.:

AF XY:

0.0000936

AC XY:

AN XY:

726794

show subpopulations

Gnomad4 AFR exome

AF:

0.000359

Gnomad4 AMR exome

AF:

0.0000896

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000756

Gnomad4 SAS exome

AF:

0.0000348

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000855

Gnomad4 OTH exome

AF:

0.000199

GnomAD4 genome

AF:

0.000151

AC:

AN:

152022

Hom.:

Cov.:

AF XY:

0.000161

AC XY:

AN XY:

74328

show subpopulations

Gnomad4 AFR

AF:

0.000289

Gnomad4 AMR

AF:

0.0000656

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000387

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000884

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.000204

EpiCase

AF:

0.000164

EpiControl

AF:

0.000297

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:6Benign:1

Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Nov 19, 2020	This variant is associated with the following publications: (PMID: 23861362) -
Uncertain significance, criteria provided, single submitter	research	Biesecker Lab/Clinical Genomics Section, National Institutes of Health	Jun 24, 2013	- -
Uncertain significance, no assertion criteria provided	clinical testing	Clinical Genetics, Academic Medical Center	-	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Mar 23, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	May 01, 2016	- -
Uncertain significance, no assertion criteria provided	clinical testing	Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)	-	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Feb 08, 2017	- -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jan 02, 2024

Variant summary: TTN c.29781_29783delAGA (p.Glu9928del) results in an in-frame deletion that is predicted to remove one amino acid from the I-band region of the encoded protein. The variant allele was found at a frequency of 0.00012 in 248470 control chromosomes (gnomAD). This frequency is not significantly higher than estimated for a pathogenic variant in TTN causing Dilated Cardiomyopathy (0.00012 vs 0.00039), allowing no conclusion about variant significance. c.29781_29783delAGA has been reported in the literature in a cohort of individuals with a spectrum of coronary artery disease risk (Ng_2013), however without strong evidence for causality (e.g., lack of clinical and co-segregation data). This report therefore does not provide unequivocal conclusions about association of the variant with Dilated Cardiomyopathy. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication was ascertained in the context of this evaluation (PMID: 23861362). Four submitters have reported clinical-significance assessments for this variant to ClinVar after 2014 with conflicting interpretations (VUS, n = 3; likely benign, n = 1). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over