NM_001267550.2:c.85745T>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4BP6

The NM_001267550.2(TTN):​c.85745T>A​(p.Ile28582Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000186 in 1,613,498 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. I28582I) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00012 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

8
5
4

Clinical Significance

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

Conservation

PhyloP100: 9.27

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 -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.37760046).
BP6
Variant 2-178560387-A-T is Benign according to our data. Variant chr2-178560387-A-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 47448.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.85745T>A p.Ile28582Lys missense_variant Exon 326 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.85745T>A p.Ile28582Lys missense_variant Exon 326 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000125
AC:
19
AN:
152048
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000459
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000322
AC:
8
AN:
248376
AF XY:
0.0000148
show subpopulations
Gnomad AFR exome
AF:
0.000517
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
AF:
0.00000753
AC:
11
AN:
1461450
Hom.:
0
Cov.:
32
AF XY:
0.00000413
AC XY:
3
AN XY:
727014
show subpopulations
African (AFR)
AF:
0.000299
AC:
10
AN:
33468
American (AMR)
AF:
0.00
AC:
0
AN:
44712
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39636
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86248
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53364
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111774
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60354
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.493
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

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:
0.000125
AC:
19
AN:
152048
Hom.:
0
Cov.:
33
AF XY:
0.000121
AC XY:
9
AN XY:
74240
show subpopulations
African (AFR)
AF:
0.000459
AC:
19
AN:
41388
American (AMR)
AF:
0.00
AC:
0
AN:
15260
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10584
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68018
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.501
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:
0.0000252
Hom.:
0
Bravo
AF:
0.000185
ESP6500AA
AF:
0.00135
AC:
5
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000497
AC:
6

ClinVar

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

Submissions by phenotype

not provided Uncertain:2
Oct 08, 2020
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 21, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Mar 06, 2013
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The Ile26014Lys in TTN has not been reported in the literature nor previously id entified by our laboratory. This variant has been identified in 0.1% (5/3696) of African American chromosomes from a broad population by the NHLBI Exome Sequenc ing Project (http://evs.gs.washington.edu/EVS/; dbSNP rs201688358). Computationa l analyses (biochemical amino acid properties, conservation, AlignGVGD, PolyPhen 2, and SIFT) suggest that this variant may impact the protein, though this infor mation is not predictive enough to determine pathogenicity. In summary, addition al information is needed to fully assess the clinical significance of this varia nt. -

Cardiovascular phenotype Benign:1
Mar 23, 2020
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.97
BayesDel_addAF
Benign
-0.048
T
BayesDel_noAF
Uncertain
0.040
CADD
Benign
21
DANN
Benign
0.90
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.99
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
D;D;D;.;D;D;D
M_CAP
Uncertain
0.28
D
MetaRNN
Benign
0.38
T;T;T;T;T;T;T
MetaSVM
Uncertain
0.52
D
MutationAssessor
Pathogenic
4.1
.;.;.;H;.;.;H
PhyloP100
9.3
PrimateAI
Uncertain
0.73
T
PROVEAN
Pathogenic
-5.1
D;D;.;.;D;D;.
REVEL
Uncertain
0.64
Sift
Pathogenic
0.0
D;D;.;.;D;D;.
Polyphen
1.0
.;.;.;D;.;.;D
Vest4
0.57
MVP
0.88
MPC
0.62
ClinPred
0.29
T
GERP RS
5.9
Mutation Taster
=77/23
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: rs201688358; hg19: chr2-179425114; API