2-178730712-T-C

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4_ModerateBP6

The NM_001267550.2(TTN):​c.17821A>G​(p.Ile5941Val) variant causes a missense change. The variant allele was found at a frequency of 0.0000192 in 1,613,654 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

3
13

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:1

Conservation

PhyloP100: 5.42

Publications

1 publications found
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: Likely_benign. The variant received -3 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.16558576).
BP6
Variant 2-178730712-T-C is Benign according to our data. Variant chr2-178730712-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 46632.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.17821A>G p.Ile5941Val missense_variant Exon 61 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.17821A>G p.Ile5941Val missense_variant Exon 61 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000657
AC:
10
AN:
152182
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000217
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000324
AC:
8
AN:
247102
AF XY:
0.0000373
show subpopulations
Gnomad AFR exome
AF:
0.000129
Gnomad AMR exome
AF:
0.000116
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000900
Gnomad OTH exome
AF:
0.000167
GnomAD4 exome
AF:
0.0000144
AC:
21
AN:
1461354
Hom.:
0
Cov.:
40
AF XY:
0.0000151
AC XY:
11
AN XY:
726950
show subpopulations
African (AFR)
AF:
0.000239
AC:
8
AN:
33460
American (AMR)
AF:
0.000134
AC:
6
AN:
44704
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26116
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39678
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86238
European-Finnish (FIN)
AF:
0.0000749
AC:
4
AN:
53378
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5760
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1111664
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60356
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000657
AC:
10
AN:
152300
Hom.:
0
Cov.:
33
AF XY:
0.0000403
AC XY:
3
AN XY:
74468
show subpopulations
African (AFR)
AF:
0.000216
AC:
9
AN:
41574
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68014
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.535
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

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:
0.000109
Hom.:
0
Bravo
AF:
0.0000529
ExAC
AF:
0.0000414
AC:
5

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Uncertain:2
Mar 22, 2012
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The Ile4697Val variant in TTN has not been reported in the literature nor previo usly identified by our laboratory. Computational analyses (biochemical amino aci d properties, conservation, AlignGVGD, and SIFT) suggest that this variant may n ot impact to the protein, though this information is not predictive enough to ru le out pathogenicity. Additional information is needed to fully assess the clini cal significance of the Ile5697Val variant. -

Dec 15, 2021
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.14089A>G (p.Ile4697Val) results in a conservative amino acid change located in the I-band domain of the encoded protein sequence. Two of three in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 3.2e-05 in 247102 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.14089A>G has been reported in the literature in an individual affected with Dilated Cardiomyopathy without strong evidence for causality (Aknrinade_2015). This report 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. One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as likely benign. Based on the evidence outlined above, the variant was classified as uncertain significance. -

not provided Uncertain:1Benign:1
Jan 16, 2019
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 24, 2020
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.10
BayesDel_addAF
Benign
-0.24
T
BayesDel_noAF
Benign
-0.34
CADD
Benign
21
DANN
Benign
0.93
Eigen
Benign
0.17
Eigen_PC
Uncertain
0.34
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Benign
0.67
T;T;.;T
M_CAP
Benign
0.027
D
MetaRNN
Benign
0.17
T;T;T;T
MetaSVM
Benign
-0.72
T
PhyloP100
5.4
PrimateAI
Uncertain
0.58
T
PROVEAN
Benign
-0.38
N;.;.;.
REVEL
Benign
0.14
Sift
Benign
0.29
T;.;.;.
Polyphen
0.51
.;.;P;P
Vest4
0.31
MVP
0.67
MPC
0.12
ClinPred
0.10
T
GERP RS
5.9
Mutation Taster
=72/28
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs397517487; hg19: chr2-179595439; API