rs34706803

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.13976A>G​(p.Tyr4659Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000809 in 1,608,126 control chromosomes in the GnomAD database, including 12 homozygotes. In-silico tool predicts 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. Y4659Y) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00079 ( 2 hom., cov: 32)
Exomes 𝑓: 0.00081 ( 10 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
6
9

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:18

Conservation

PhyloP100: 8.02

Publications

8 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 -16 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.0087429285).
BP6
Variant 2-178739257-T-C is Benign according to our data. Variant chr2-178739257-T-C is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 166228.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.13976A>G p.Tyr4659Cys 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.13976A>G p.Tyr4659Cys missense_variant Exon 48 of 363 5 NM_001267550.2 ENSP00000467141.1

Frequencies

GnomAD3 genomes
AF:
0.000788
AC:
120
AN:
152226
Hom.:
2
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.0276
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000265
Gnomad OTH
AF:
0.00143
GnomAD2 exomes
AF:
0.00145
AC:
358
AN:
246586
AF XY:
0.00146
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.0318
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000295
Gnomad OTH exome
AF:
0.00185
GnomAD4 exome
AF:
0.000811
AC:
1181
AN:
1455900
Hom.:
10
Cov.:
30
AF XY:
0.000837
AC XY:
605
AN XY:
723196
show subpopulations
African (AFR)
AF:
0.0000300
AC:
1
AN:
33352
American (AMR)
AF:
0.0000225
AC:
1
AN:
44520
Ashkenazi Jewish (ASJ)
AF:
0.0343
AC:
889
AN:
25950
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39458
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85812
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53206
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5746
European-Non Finnish (NFE)
AF:
0.000135
AC:
150
AN:
1107730
Other (OTH)
AF:
0.00233
AC:
140
AN:
60126
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.496
Heterozygous variant carriers
0
67
133
200
266
333
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
22
44
66
88
110
<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:
0.000788
AC:
120
AN:
152226
Hom.:
2
Cov.:
32
AF XY:
0.000740
AC XY:
55
AN XY:
74358
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41464
American (AMR)
AF:
0.000131
AC:
2
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.0276
AC:
96
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000265
AC:
18
AN:
68038
Other (OTH)
AF:
0.00143
AC:
3
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.498
Heterozygous variant carriers
0
7
15
22
30
37
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:
0.00138
Hom.:
4
Bravo
AF:
0.000846
TwinsUK
AF:
0.00162
AC:
6
ALSPAC
AF:
0.000519
AC:
2
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.00133
AC:
11
ExAC
AF:
0.00117
AC:
141

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:18
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:6
-
Clinical Genetics, Academic Medical Center
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Dec 01, 2020
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 24, 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. -

May 10, 2019
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

proposed classification - variant undergoing re-assessment, contact laboratory -

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

- -

Jan 06, 2017
Eurofins Ntd Llc (ga)
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:3
Jun 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

TTN: BS1 -

-
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

- -

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

- -

TTN-related disorder Benign:1
Mar 14, 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 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
Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiomyopathy Benign:1
May 02, 2018
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
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

- -

Primary dilated cardiomyopathy Benign:1
Apr 06, 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

- -

Cardiovascular phenotype Benign:1
Feb 22, 2018
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
0.25
BayesDel_addAF
Benign
-0.37
T
BayesDel_noAF
Benign
-0.33
CADD
Benign
19
DANN
Benign
0.75
Eigen
Uncertain
0.56
Eigen_PC
Uncertain
0.51
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.86
D;D;.;D;D;D
M_CAP
Benign
0.028
D
MetaRNN
Benign
0.0087
T;T;T;T;T;T
MetaSVM
Benign
-0.58
T
PhyloP100
8.0
PrimateAI
Uncertain
0.63
T
PROVEAN
Uncertain
-3.9
D;.;.;D;D;.
REVEL
Uncertain
0.51
Sift
Benign
0.17
T;.;.;T;T;.
Vest4
0.82
MVP
0.43
MPC
0.51
ClinPred
0.12
T
GERP RS
5.8
Mutation Taster
=69/31
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: rs34706803; hg19: chr2-179603984; COSMIC: COSV104645788; API