2-178679958-CTCTTCT-CTCT

Variant summary

Our verdict is Uncertain significance. The variant received 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-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]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 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
TTNNM_001267550.2 linkc.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
TTNENST00000589042.5 linkc.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:
23
AN:
151904
Hom.:
0
Cov.:
32
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
GnomAD2 exomes
AF:
0.000125
AC:
31
AN:
248470
AF XY:
0.000148
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 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.:
1
AF XY:
0.0000936
AC XY:
68
AN XY:
726794
show subpopulations
Gnomad4 AFR exome
AF:
0.000359
AC:
12
AN:
33444
Gnomad4 AMR exome
AF:
0.0000896
AC:
4
AN:
44646
Gnomad4 ASJ exome
AF:
0.00
AC:
0
AN:
26102
Gnomad4 EAS exome
AF:
0.0000756
AC:
3
AN:
39694
Gnomad4 SAS exome
AF:
0.0000348
AC:
3
AN:
86216
Gnomad4 FIN exome
AF:
0.00
AC:
0
AN:
53394
Gnomad4 NFE exome
AF:
0.0000855
AC:
95
AN:
1111372
Gnomad4 Remaining exome
AF:
0.000199
AC:
12
AN:
60352
Heterozygous variant carriers
0
7
15
22
30
37
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Exome Het
Exome Hom
Variant carriers
0
4
8
12
16
20
<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:
0.000151
AC:
23
AN:
152022
Hom.:
0
Cov.:
32
AF XY:
0.000161
AC XY:
12
AN XY:
74328
show subpopulations
Gnomad4 AFR
AF:
0.000289
AC:
0.000289143
AN:
0.000289143
Gnomad4 AMR
AF:
0.0000656
AC:
0.000065634
AN:
0.000065634
Gnomad4 ASJ
AF:
0.00
AC:
0
AN:
0
Gnomad4 EAS
AF:
0.000387
AC:
0.000386997
AN:
0.000386997
Gnomad4 SAS
AF:
0.00
AC:
0
AN:
0
Gnomad4 FIN
AF:
0.00
AC:
0
AN:
0
Gnomad4 NFE
AF:
0.0000884
AC:
0.0000883522
AN:
0.0000883522
Gnomad4 OTH
AF:
0.00
AC:
0
AN:
0
Heterozygous variant carriers
0
2
3
5
6
8
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Genome 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
Alfa
AF:
0.0000368
Hom.:
0
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
Feb 08, 2017
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Clinical Genetics, Academic Medical Center
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Nov 19, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 23861362) -

Jun 24, 2013
Biesecker Lab/Clinical Genomics Section, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

- -

May 01, 2016
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 23, 2023
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Jan 02, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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
Mutation Taster
=87/13
polymorphism

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.

Other links and lift over

dbSNP: rs368327166; hg19: chr2-179544685; API