2-178662348-T-C

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_StrongBP6BP7

The NM_001267550.2(TTN):​c.37029A>G​(p.Pro12343Pro) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. P12343P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000047 ( 0 hom., cov: 16)
Exomes 𝑓: 0.00039 ( 24 hom. )
Failed GnomAD Quality Control

Consequence

TTN
NM_001267550.2 synonymous

Scores

2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:4

Conservation

PhyloP100: -3.47

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 -6 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.91).
BP6
Variant 2-178662348-T-C is Benign according to our data. Variant chr2-178662348-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 404763.
BP7
Synonymous conserved (PhyloP=-3.47 with no splicing effect.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.37029A>G p.Pro12343Pro synonymous_variant Exon 177 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.37029A>G p.Pro12343Pro synonymous_variant Exon 177 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000474
AC:
6
AN:
126482
Hom.:
0
Cov.:
16
show subpopulations
Gnomad AFR
AF:
0.0000306
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000174
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.000115
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000324
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00
AC:
0
AN:
198662
AF XY:
0.00
Gnomad AFR exome
AF:
0.00
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
Data not reliable, filtered out with message: AS_VQSR
AF:
0.000393
AC:
532
AN:
1353126
Hom.:
24
Cov.:
31
AF XY:
0.000415
AC XY:
279
AN XY:
672250
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.000327
AC:
10
AN:
30594
American (AMR)
AF:
0.000882
AC:
34
AN:
38558
Ashkenazi Jewish (ASJ)
AF:
0.0000811
AC:
2
AN:
24676
East Asian (EAS)
AF:
0.000716
AC:
23
AN:
32114
South Asian (SAS)
AF:
0.000649
AC:
46
AN:
70856
European-Finnish (FIN)
AF:
0.000880
AC:
32
AN:
36352
Middle Eastern (MID)
AF:
0.00104
AC:
4
AN:
3844
European-Non Finnish (NFE)
AF:
0.000332
AC:
352
AN:
1060220
Other (OTH)
AF:
0.000519
AC:
29
AN:
55912
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.378
Heterozygous variant carriers
0
44
88
131
175
219
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
20
40
60
80
100
<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:
0.0000474
AC:
6
AN:
126544
Hom.:
0
Cov.:
16
AF XY:
0.0000495
AC XY:
3
AN XY:
60644
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000305
AC:
1
AN:
32746
American (AMR)
AF:
0.000174
AC:
2
AN:
11472
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3108
East Asian (EAS)
AF:
0.00
AC:
0
AN:
3316
South Asian (SAS)
AF:
0.00
AC:
0
AN:
2920
European-Finnish (FIN)
AF:
0.000115
AC:
1
AN:
8732
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
268
European-Non Finnish (NFE)
AF:
0.0000324
AC:
2
AN:
61658
Other (OTH)
AF:
0.00
AC:
0
AN:
1714
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.242
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:
0.000506
Hom.:
0

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:4
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Benign:4
-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Genome Diagnostics Laboratory, University Medical Center Utrecht
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Aug 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

TTN: BP4, BP7 -

-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Dec 21, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.91
CADD
Benign
0.072
DANN
Benign
0.30
PhyloP100
-3.5
Mutation Taster
=100/0
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: rs200163049; hg19: chr2-179527075; API