rs149470241

Variant summary

Our verdict is Benign. The variant received -11 ACMG points: 0P and 11B. BP4_ModerateBP6BS1BS2

The NM_001267550.2(TTN):​c.20335A>T​(p.Ser6779Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00153 in 1,603,862 control chromosomes in the GnomAD database, including 3 homozygotes. In-silico tool predicts a benign outcome for this variant. 12/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00060 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0016 ( 3 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
5
10

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:16

Conservation

PhyloP100: 2.77

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 -11 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.07339355).
BP6
Variant 2-178725987-T-A is Benign according to our data. Variant chr2-178725987-T-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 46670.
BS1
Variant frequency is greater than expected in population nfe. GnomAdExome4 allele frequency = 0.00163 (2363/1451598) while in subpopulation NFE AF = 0.00208 (2299/1106278). AF 95% confidence interval is 0.00201. There are 3 homozygotes in GnomAdExome4. There are 1146 alleles in the male GnomAdExome4 subpopulation. Median coverage is 31. This position passed quality control check.
BS2
High Homozygotes in GnomAdExome4 at 3 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.20335A>T p.Ser6779Cys missense_variant Exon 70 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.20335A>T p.Ser6779Cys missense_variant Exon 70 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000598
AC:
91
AN:
152146
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000362
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000197
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:
0.00107
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000588
AC:
142
AN:
241612
AF XY:
0.000595
show subpopulations
Gnomad AFR exome
AF:
0.000332
Gnomad AMR exome
AF:
0.0000920
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00120
Gnomad OTH exome
AF:
0.000347
GnomAD4 exome
AF:
0.00163
AC:
2363
AN:
1451598
Hom.:
3
Cov.:
31
AF XY:
0.00159
AC XY:
1146
AN XY:
721142
show subpopulations
African (AFR)
AF:
0.000272
AC:
9
AN:
33058
American (AMR)
AF:
0.0000685
AC:
3
AN:
43806
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25876
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39300
South Asian (SAS)
AF:
0.0000118
AC:
1
AN:
84402
European-Finnish (FIN)
AF:
0.0000564
AC:
3
AN:
53198
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5712
European-Non Finnish (NFE)
AF:
0.00208
AC:
2299
AN:
1106278
Other (OTH)
AF:
0.000800
AC:
48
AN:
59968
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.491
Heterozygous variant carriers
0
144
288
432
576
720
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
98
196
294
392
490
<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:
0.000598
AC:
91
AN:
152264
Hom.:
0
Cov.:
33
AF XY:
0.000537
AC XY:
40
AN XY:
74444
show subpopulations
African (AFR)
AF:
0.000361
AC:
15
AN:
41576
American (AMR)
AF:
0.000196
AC:
3
AN:
15270
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5168
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00107
AC:
73
AN:
68006
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.487
Heterozygous variant carriers
0
5
10
15
20
25
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:
0.00117
Hom.:
0
Bravo
AF:
0.000623
TwinsUK
AF:
0.00243
AC:
9
ALSPAC
AF:
0.00311
AC:
12
ESP6500AA
AF:
0.000269
AC:
1
ESP6500EA
AF:
0.000487
AC:
4
ExAC
AF:
0.000580
AC:
70

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:6Benign:16
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3Benign:8
May 05, 2020
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The TTN c.16603A>T; p.Ser5535Cys variant is rare in the general population (<1% allele frequency in the Genome Aggregation Database) and has not been reported in the medical literature in association with dilated cardiomyopathy (DCM) or other TTN-related disease. The clinical relevance of rare missense variants in this gene, which are identified on average once per individual sequenced in affected populations (Herman 2012), is not well understood. Yet, evidence suggests that the vast majority of such missense variants do not contribute to the clinical outcome of DCM (Begay 2015). Thus, the clinical significance of the p.Ser5535Cys variant cannot be determined with certainty. References: Begay RL et al. Role of Titin Missense Variants in Dilated Cardiomyopathy. J Am Heart Assoc. 2015 Nov 13;4(11). Herman DS et al. Truncations of titin causing dilated cardiomyopathy. N Engl J Med. 2012 Feb 16;366(7):619-28. -

Dec 04, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 23861362) -

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

- -

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

- -

May 16, 2018
Athena Diagnostics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Genome Diagnostics Laboratory, University Medical Center Utrecht
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

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

- -

Jan 14, 2016
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 26, 2023
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

TTN: BP1, BP4 -

not specified Benign:3
Nov 26, 2018
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.Ser5535Cys variant in TTN is classified as likely benign because it has be en identified in 0.1% (142/124290) of European chromosomes by gnomAD (http://gno mad.broadinstitute.org). ACMG/AMP Criteria applied: BS1. -

Apr 09, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J Uncertain:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Dilated cardiomyopathy 1G Uncertain:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Early-onset myopathy with fatal cardiomyopathy Uncertain:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

TTN-related disorder Benign:1
Oct 12, 2020
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely 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
Jan 31, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiomyopathy Benign:1
Aug 09, 2019
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Tibial muscular dystrophy Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Myopathy, myofibrillar, 9, with early respiratory failure Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.14
BayesDel_addAF
Benign
-0.34
T
BayesDel_noAF
Benign
-0.27
CADD
Benign
22
DANN
Benign
0.86
Eigen
Uncertain
0.54
Eigen_PC
Uncertain
0.51
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.68
T;T;.;T
M_CAP
Benign
0.075
D
MetaRNN
Benign
0.073
T;T;T;T
MetaSVM
Uncertain
-0.073
T
PhyloP100
2.8
PrimateAI
Benign
0.46
T
PROVEAN
Uncertain
-2.7
D;.;.;.
REVEL
Uncertain
0.50
Sift
Benign
0.033
D;.;.;.
Polyphen
0.99
.;.;D;D
Vest4
0.26
MVP
0.56
MPC
0.37
ClinPred
0.046
T
GERP RS
4.7
Mutation Taster
=80/20
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: rs149470241; hg19: chr2-179590714; API