NM_001267550.2:c.54718G>A

Variant summary

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

The NM_001267550.2(TTN):​c.54718G>A​(p.Val18240Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000521 in 1,612,680 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/20 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 0.00018 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000038 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:2

Conservation

PhyloP100: 4.62

Publications

2 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=0.12154776).
BP6
Variant 2-178603969-C-T is Benign according to our data. Variant chr2-178603969-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 283028.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.54718G>A p.Val18240Ile missense_variant Exon 282 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.54718G>A p.Val18240Ile missense_variant Exon 282 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000184
AC:
28
AN:
151904
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000531
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00949
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000241
AC:
6
AN:
248550
AF XY:
0.0000148
show subpopulations
Gnomad AFR exome
AF:
0.000259
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000178
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000383
AC:
56
AN:
1460658
Hom.:
0
Cov.:
31
AF XY:
0.0000317
AC XY:
23
AN XY:
726630
show subpopulations
African (AFR)
AF:
0.000688
AC:
23
AN:
33408
American (AMR)
AF:
0.0000224
AC:
1
AN:
44700
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26100
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39638
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86188
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53388
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5754
European-Non Finnish (NFE)
AF:
0.0000189
AC:
21
AN:
1111170
Other (OTH)
AF:
0.000166
AC:
10
AN:
60312
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
3
7
10
14
17
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:
0.000184
AC:
28
AN:
152022
Hom.:
0
Cov.:
32
AF XY:
0.000202
AC XY:
15
AN XY:
74286
show subpopulations
African (AFR)
AF:
0.000530
AC:
22
AN:
41526
American (AMR)
AF:
0.000131
AC:
2
AN:
15250
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5114
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10598
Middle Eastern (MID)
AF:
0.0102
AC:
3
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67926
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.487
Heterozygous variant carriers
0
1
2
4
5
6
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:
0.000149
Hom.:
0
Bravo
AF:
0.000117
ESP6500AA
AF:
0.000261
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2Benign:1
Sep 15, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 14, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jun 18, 2019
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Oct 28, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1
Apr 09, 2025
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.077
BayesDel_addAF
Benign
-0.39
T
BayesDel_noAF
Benign
-0.42
CADD
Benign
21
DANN
Benign
0.93
Eigen
Benign
0.051
Eigen_PC
Benign
0.19
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Benign
0.86
D;D;D;.;T;D;T
M_CAP
Benign
0.020
T
MetaRNN
Benign
0.12
T;T;T;T;T;T;T
MetaSVM
Benign
-0.71
T
MutationAssessor
Benign
1.3
.;.;.;L;.;.;L
PhyloP100
4.6
PrimateAI
Benign
0.41
T
PROVEAN
Benign
-0.68
N;N;.;.;N;N;.
REVEL
Benign
0.11
Sift
Benign
0.32
T;T;.;.;T;T;.
Polyphen
0.21
.;.;.;B;.;.;B
Vest4
0.29
MVP
0.43
MPC
0.092
ClinPred
0.066
T
GERP RS
5.2
Mutation Taster
=96/4
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

Other links and lift over

dbSNP: rs375141729; hg19: chr2-179468696; COSMIC: COSV59954132; COSMIC: COSV59954132; API