2-178717809-C-T

Variant summary

Our verdict is Benign. The variant received -11 ACMG points: 0P and 11B. BP4_ModerateBP6_Very_StrongBP7

The NM_001267550.2(TTN):​c.25065G>A​(p.Ala8355Ala) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000355 in 1,603,890 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 Likely benign (★★).

Frequency

Genomes: 𝑓 0.00011 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000028 ( 0 hom. )

Consequence

TTN
NM_001267550.2 splice_region, synonymous

Scores

2
Splicing: ADA: 0.0001246
2

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:6

Conservation

PhyloP100: -0.170

Publications

0 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: Benign. The variant received -11 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.44).
BP6
Variant 2-178717809-C-T is Benign according to our data. Variant chr2-178717809-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 46751.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=-0.17 with no splicing effect.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.25065G>A p.Ala8355Ala splice_region_variant, synonymous_variant Exon 87 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.25065G>A p.Ala8355Ala splice_region_variant, synonymous_variant Exon 87 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000112
AC:
17
AN:
152076
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000338
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:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000417
AC:
10
AN:
239942
AF XY:
0.0000230
show subpopulations
Gnomad AFR exome
AF:
0.000330
Gnomad AMR exome
AF:
0.0000599
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000277
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000276
AC:
40
AN:
1451696
Hom.:
0
Cov.:
34
AF XY:
0.0000291
AC XY:
21
AN XY:
721098
show subpopulations
African (AFR)
AF:
0.000426
AC:
14
AN:
32890
American (AMR)
AF:
0.0000919
AC:
4
AN:
43520
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25716
East Asian (EAS)
AF:
0.0000253
AC:
1
AN:
39572
South Asian (SAS)
AF:
0.0000473
AC:
4
AN:
84652
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52866
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5690
European-Non Finnish (NFE)
AF:
0.0000126
AC:
14
AN:
1106890
Other (OTH)
AF:
0.0000501
AC:
3
AN:
59900
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.456
Heterozygous variant carriers
0
3
5
8
10
13
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:
0.000112
AC:
17
AN:
152194
Hom.:
0
Cov.:
33
AF XY:
0.000108
AC XY:
8
AN XY:
74400
show subpopulations
African (AFR)
AF:
0.000337
AC:
14
AN:
41544
American (AMR)
AF:
0.000131
AC:
2
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5172
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
292
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67978
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.519
Heterozygous variant carriers
0
2
3
5
6
8
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:
0.000168
Hom.:
0
Bravo
AF:
0.000162

ClinVar

Significance: Likely benign
Submissions summary: Benign:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:3
-
Clinical Genetics, Academic Medical Center
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Jan 26, 2016
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

p.Ala7111Ala in exon 84 of TTN: This variant is not expected to have clinical s ignificance because it does not alter an amino acid residue and is not located w ithin the splice consensus sequence. It has been identified in 3/9382 African ch romosomes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute. org; dbSNP rs397517514). -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Benign:1
Dec 27, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiomyopathy Benign:1
Mar 23, 2022
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:1
Apr 23, 2021
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.44
CADD
Benign
7.4
DANN
Benign
0.78
PhyloP100
-0.17
Mutation Taster
=67/33
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.00012
dbscSNV1_RF
Benign
0.014
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: rs397517514; hg19: chr2-179582536; COSMIC: COSV60024067; COSMIC: COSV60024067; API