rs80136515

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_001267550.2(TTN):​c.12233C>T​(p.Thr4078Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000804 in 1,613,886 control chromosomes in the GnomAD database, including 13 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/18 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. T4078T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0043 ( 3 hom., cov: 32)
Exomes 𝑓: 0.00044 ( 10 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

15

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:19

Conservation

PhyloP100: 0.954

Publications

5 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 -20 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.0034502745).
BP6
Variant 2-178741000-G-A is Benign according to our data. Variant chr2-178741000-G-A is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 47821.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00427 (651/152286) while in subpopulation AFR AF = 0.0148 (613/41552). AF 95% confidence interval is 0.0138. There are 3 homozygotes in GnomAd4. There are 333 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 3 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.12233C>T p.Thr4078Ile missense_variant Exon 48 of 363 ENST00000589042.5 NP_001254479.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.12233C>T p.Thr4078Ile missense_variant Exon 48 of 363 5 NM_001267550.2 ENSP00000467141.1

Frequencies

GnomAD3 genomes
AF:
0.00424
AC:
645
AN:
152168
Hom.:
3
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0147
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00157
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:
0.0000588
Gnomad OTH
AF:
0.00478
GnomAD2 exomes
AF:
0.00100
AC:
249
AN:
248262
AF XY:
0.000802
show subpopulations
Gnomad AFR exome
AF:
0.0137
Gnomad AMR exome
AF:
0.000725
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000446
Gnomad OTH exome
AF:
0.000829
GnomAD4 exome
AF:
0.000442
AC:
646
AN:
1461600
Hom.:
10
Cov.:
32
AF XY:
0.000369
AC XY:
268
AN XY:
727086
show subpopulations
African (AFR)
AF:
0.0156
AC:
523
AN:
33474
American (AMR)
AF:
0.000827
AC:
37
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39686
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53400
Middle Eastern (MID)
AF:
0.000347
AC:
2
AN:
5764
European-Non Finnish (NFE)
AF:
0.0000126
AC:
14
AN:
1111800
Other (OTH)
AF:
0.00111
AC:
67
AN:
60368
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.482
Heterozygous variant carriers
0
47
94
142
189
236
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:
0.00427
AC:
651
AN:
152286
Hom.:
3
Cov.:
32
AF XY:
0.00447
AC XY:
333
AN XY:
74454
show subpopulations
African (AFR)
AF:
0.0148
AC:
613
AN:
41552
American (AMR)
AF:
0.00157
AC:
24
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68020
Other (OTH)
AF:
0.00473
AC:
10
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
32
64
96
128
160
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome 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
Alfa
AF:
0.00130
Hom.:
3
Bravo
AF:
0.00497
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ESP6500AA
AF:
0.0134
AC:
50
ESP6500EA
AF:
0.000244
AC:
2
ExAC
AF:
0.00118
AC:
143
Asia WGS
AF:
0.000577
AC:
2
AN:
3478
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:19
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:7
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

- -

-
Clinical Genetics, Academic Medical Center
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Mar 02, 2012
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Thr3840Ile in exon 45B of TTN: This variant is not expected to have clinical sig nificance because it has been identified in 1.3% (38/3022) of African American c hromosomes from a broad population by the NHLBI Exome Sequencing Project (http:/ /evs.gs.washington.edu/EVS; dbSNP rs80136515). -

May 01, 2014
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. -

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

- -

Oct 17, 2023
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jun 24, 2013
Biesecker Lab/Clinical Genomics Section, National Institutes of Health
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:research

- -

not provided Benign:3
Feb 08, 2022
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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

- -

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

TTN: BP4, BS1, BS2 -

Cardiomyopathy Benign:2
Mar 09, 2016
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 23, 2018
Center for Advanced Laboratory Medicine, UC San Diego Health, University of California San Diego
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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

- -

TTN-related disorder Benign:1
May 29, 2019
PreventionGenetics, part of Exact Sciences
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Benign:1
Feb 02, 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

- -

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

- -

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

- -

Cardiovascular phenotype Benign:1
Jul 19, 2016
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as 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
Benign
0.26
BayesDel_addAF
Benign
-0.50
T
BayesDel_noAF
Benign
-0.48
CADD
Benign
12
DANN
Benign
0.58
Eigen
Benign
-0.52
Eigen_PC
Benign
-0.47
FATHMM_MKL
Benign
0.099
N
LIST_S2
Benign
0.73
T;T;.;T;T;T
MetaRNN
Benign
0.0035
T;T;T;T;T;T
MetaSVM
Benign
-1.0
T
PhyloP100
0.95
PrimateAI
Benign
0.30
T
PROVEAN
Benign
-1.6
N;.;.;N;N;.
REVEL
Benign
0.059
Sift
Benign
0.076
T;.;.;T;D;.
Vest4
0.21
MVP
0.25
MPC
0.093
ClinPred
0.0036
T
GERP RS
5.4
Mutation Taster
=91/9
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: rs80136515; hg19: chr2-179605727; COSMIC: COSV59981546; API