NM_001267550.2:c.87805G>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.87805G>A​(p.Val29269Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000297 in 1,613,960 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/20 in silico tools predict 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. V29269V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
16

Clinical Significance

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

Conservation

PhyloP100: 2.63

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=0.106711954).
BP6
Variant 2-178557457-C-T is Benign according to our data. Variant chr2-178557457-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 165769.We mark this variant Likely_benign, oryginal submission is: [Conflicting_classifications_of_pathogenicity].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.87805G>A p.Val29269Ile missense_variant Exon 329 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.87805G>A p.Val29269Ile missense_variant Exon 329 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000328
AC:
5
AN:
152214
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.00633
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000322
AC:
8
AN:
248732
AF XY:
0.0000371
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000355
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000294
AC:
43
AN:
1461628
Hom.:
0
Cov.:
33
AF XY:
0.0000358
AC XY:
26
AN XY:
727090
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39676
South Asian (SAS)
AF:
0.0000580
AC:
5
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53398
Middle Eastern (MID)
AF:
0.00121
AC:
7
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000234
AC:
26
AN:
1111824
Other (OTH)
AF:
0.0000663
AC:
4
AN:
60372
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.487
Heterozygous variant carriers
0
3
6
10
13
16
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:
0.0000328
AC:
5
AN:
152332
Hom.:
0
Cov.:
33
AF XY:
0.0000403
AC XY:
3
AN XY:
74490
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41576
American (AMR)
AF:
0.00
AC:
0
AN:
15302
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5174
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00680
AC:
2
AN:
294
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.545
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.00
Hom.:
0
Bravo
AF:
0.0000264
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

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

Submissions by phenotype

not provided Uncertain:3Benign:1
May 01, 2018
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Oct 11, 2019
Revvity Omics, Revvity
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

- -

not specified Uncertain:1
Aug 15, 2013
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The Val26701Ile variant in TTN has not been reported in individuals with cardiom yopathy or in large population studies. Computational analyses (biochemical amin o acid properties, conservation, AlignGVGD, PolyPhen2, and SIFT) do not provide strong support for or against an impact to the protein. Additional information i s needed to fully assess the clinical significance of the Val26701Ile variant. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.077
BayesDel_addAF
Benign
-0.33
T
BayesDel_noAF
Benign
-0.51
CADD
Benign
17
DANN
Benign
0.87
Eigen
Benign
-0.079
Eigen_PC
Benign
0.16
FATHMM_MKL
Uncertain
0.89
D
LIST_S2
Benign
0.84
T;T;T;.;T;T;T
M_CAP
Benign
0.023
T
MetaRNN
Benign
0.11
T;T;T;T;T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
-0.58
.;.;.;N;.;.;N
PhyloP100
2.6
PrimateAI
Benign
0.32
T
PROVEAN
Benign
-0.62
N;N;.;.;N;N;.
REVEL
Benign
0.074
Sift
Benign
0.24
T;T;.;.;T;T;.
Polyphen
0.12
.;.;.;B;.;.;B
Vest4
0.20
MutPred
0.41
.;.;.;Gain of catalytic residue at L27633 (P = 0.0318);.;.;Gain of catalytic residue at L27633 (P = 0.0318);
MVP
0.42
MPC
0.081
ClinPred
0.052
T
GERP RS
5.6
Mutation Taster
=71/29
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: rs727503551; hg19: chr2-179422184; API