NM_001267550.2:c.289G>A

Variant summary

Our verdict is Benign. The variant received -16 ACMG points: 0P and 16B. BP4_StrongBP6_Very_StrongBS2

The NM_001267550.2(TTN):​c.289G>A​(p.Val97Met) variant causes a missense change. The variant allele was found at a frequency of 0.00117 in 1,614,088 control chromosomes in the GnomAD database, including 18 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0020 ( 2 hom., cov: 32)
Exomes 𝑓: 0.0011 ( 16 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

4
6
6

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:13

Conservation

PhyloP100: 6.09

Publications

7 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 Gene-Disease associations (from GenCC):
  • dilated cardiomyopathy
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • dilated cardiomyopathy 1G
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P
  • early-onset myopathy with fatal cardiomyopathy
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, G2P
  • TTN-related myopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • myopathy, myofibrillar, 9, with early respiratory failure
    Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, ClinGen, Ambry Genetics
  • tibial muscular dystrophy
    Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen, Orphanet
  • autosomal recessive limb-girdle muscular dystrophy type 2J
    Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet
  • hypertrophic cardiomyopathy 9
    Inheritance: AD Classification: MODERATE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia
  • familial isolated dilated cardiomyopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • autosomal recessive centronuclear myopathy
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • childhood-onset progressive contractures-limb-girdle weakness-muscle dystrophy syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • arrhythmogenic right ventricular cardiomyopathy
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen
  • congenital myopathy
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • hereditary skeletal muscle disorder
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • hypertrophic cardiomyopathy
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -16 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.008271962).
BP6
Variant 2-178802144-C-T is Benign according to our data. Variant chr2-178802144-C-T is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 178278.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS2
High Homozygotes in GnomAd4 at 2 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.289G>A p.Val97Met missense_variant Exon 3 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7
TTNNM_133379.5 linkc.289G>A p.Val97Met missense_variant Exon 3 of 46 ENST00000360870.10 NP_596870.2 Q8WZ42-6Q7Z3B7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.289G>A p.Val97Met missense_variant Exon 3 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7
TTNENST00000360870.10 linkc.289G>A p.Val97Met missense_variant Exon 3 of 46 5 NM_133379.5 ENSP00000354117.4 Q8WZ42-6

Frequencies

GnomAD3 genomes
AF:
0.00199
AC:
303
AN:
152160
Hom.:
2
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000169
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00115
Gnomad EAS
AF:
0.000770
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0234
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000559
Gnomad OTH
AF:
0.000955
GnomAD2 exomes
AF:
0.00238
AC:
599
AN:
251394
AF XY:
0.00230
show subpopulations
Gnomad AFR exome
AF:
0.000246
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.000893
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0227
Gnomad NFE exome
AF:
0.000642
Gnomad OTH exome
AF:
0.00342
GnomAD4 exome
AF:
0.00109
AC:
1591
AN:
1461810
Hom.:
16
Cov.:
32
AF XY:
0.00108
AC XY:
787
AN XY:
727210
show subpopulations
African (AFR)
AF:
0.000209
AC:
7
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.000689
AC:
18
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39694
South Asian (SAS)
AF:
0.0000464
AC:
4
AN:
86250
European-Finnish (FIN)
AF:
0.0246
AC:
1313
AN:
53416
Middle Eastern (MID)
AF:
0.000696
AC:
4
AN:
5746
European-Non Finnish (NFE)
AF:
0.000158
AC:
176
AN:
1111972
Other (OTH)
AF:
0.00111
AC:
67
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.485
Heterozygous variant carriers
0
93
186
280
373
466
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
10
20
30
40
50
<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:
0.00199
AC:
303
AN:
152278
Hom.:
2
Cov.:
32
AF XY:
0.00269
AC XY:
200
AN XY:
74444
show subpopulations
African (AFR)
AF:
0.000168
AC:
7
AN:
41556
American (AMR)
AF:
0.00
AC:
0
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00115
AC:
4
AN:
3470
East Asian (EAS)
AF:
0.000772
AC:
4
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.0234
AC:
248
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000559
AC:
38
AN:
68018
Other (OTH)
AF:
0.000945
AC:
2
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.501
Heterozygous variant carriers
0
17
33
50
66
83
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
4
8
12
16
20
<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:
0.000474
Hom.:
1
Bravo
AF:
0.000166
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000349
AC:
3
ExAC
AF:
0.00208
AC:
253
Asia WGS
AF:
0.000866
AC:
3
AN:
3478
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000178

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:13
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:5
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

- -

Jan 24, 2017
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 10, 2014
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Val97Met in exon 3 of TTN: This variant is not expected to have clinical signifi cance because it has been identified in 2.2% (4/186) of Finnish chromosomes by t he 1000 Genomes Project (dbSNP rs185921345). -

Jan 30, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: TTN c.289G>A (p.Val97Met) results in a conservative amino acid change located in the Z-disk region of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.0012 in 1614088 control chromosomes in the gnomAD database, including 18 homozygotes, and is found predominantly within individuals of Finnish ancestry at a frequency of 0.024. The observed variant frequency in the gnomAD database is approximately 3-fold of the estimated maximal expected allele frequency for a pathogenic variant in TTN causing Dilated Cardiomyopathy phenotype (0.00039), strongly suggesting that the variant is benign. c.289G>A has been reported in the literature without evidence for causality in an individual affected with arrhythmogenic right ventricular cardiomyopathy and in an individual who suffered a sudden unexplained death and was found to have hypertrophic cardiomyopathy (Campuzano_2015, Sanchez_2016). These reports do not provide unequivocal conclusions about association of the variant with Dilated Cardiomyopathy. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. ClinVar contains an entry for this variant (Variation ID: 178278). Based on the evidence outlined above, the variant was classified as benign. -

Oct 31, 2017
GeneDx
Significance: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. -

not provided Benign:2
Dec 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

TTN: BS2 -

-
Breakthrough Genomics, Breakthrough Genomics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J Benign:1
Sep 10, 2021
Genome-Nilou Lab
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Benign:1
Jan 23, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Early-onset myopathy with fatal cardiomyopathy Benign:1
Sep 10, 2021
Genome-Nilou Lab
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Tibial muscular dystrophy Benign:1
Sep 10, 2021
Genome-Nilou Lab
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Myopathy, myofibrillar, 9, with early respiratory failure Benign:1
Sep 10, 2021
Genome-Nilou Lab
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Benign:1
Mar 26, 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
0.88
BayesDel_addAF
Benign
-0.22
T
BayesDel_noAF
Benign
-0.090
CADD
Uncertain
25
DANN
Benign
0.96
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.95
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Pathogenic
0.99
D;D;D;.;D;D;D;D
MetaRNN
Benign
0.0083
T;T;T;T;T;T;T;T
MetaSVM
Uncertain
0.78
D
PhyloP100
6.1
PrimateAI
Uncertain
0.67
T
PROVEAN
Benign
-1.8
N;N;.;.;N;N;.;N
REVEL
Uncertain
0.62
Sift
Uncertain
0.0040
D;D;.;.;D;D;.;D
Sift4G
Uncertain
0.0020
.;.;.;.;.;.;.;D
Polyphen
1.0
.;.;.;D;.;.;D;D
Vest4
0.44
MVP
0.76
MPC
0.45
ClinPred
0.054
T
GERP RS
5.7
Mutation Taster
=95/5
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: rs185921345; hg19: chr2-179666871; COSMIC: COSV59907202; COSMIC: COSV59907202; API