rs199875474

Variant summary

Our verdict is Benign. The variant received -14 ACMG points: 0P and 14B. BP4_StrongBP6BP7BS1BS2

The NM_001267550.2(TTN):​c.80271C>T​(p.Val26757Val) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000726 in 1,613,612 control chromosomes in the GnomAD database, including 8 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00051 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00075 ( 8 hom. )

Consequence

TTN
NM_001267550.2 synonymous

Scores

2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:17

Conservation

PhyloP100: -0.131

Publications

0 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 -14 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.77).
BP6
Variant 2-178565861-G-A is Benign according to our data. Variant chr2-178565861-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 47384.
BP7
Synonymous conserved (PhyloP=-0.131 with no splicing effect.
BS1
Variant frequency is greater than expected in population sas. GnomAd4 allele frequency = 0.000506 (77/152206) while in subpopulation SAS AF = 0.00664 (32/4820). AF 95% confidence interval is 0.00483. There are 0 homozygotes in GnomAd4. There are 44 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High Homozygotes in GnomAdExome4 at 8 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.80271C>T p.Val26757Val synonymous_variant Exon 326 of 363 ENST00000589042.5 NP_001254479.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.80271C>T p.Val26757Val synonymous_variant Exon 326 of 363 5 NM_001267550.2 ENSP00000467141.1

Frequencies

GnomAD3 genomes
AF:
0.000500
AC:
76
AN:
152088
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.00980
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00643
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00316
Gnomad NFE
AF:
0.000103
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00158
AC:
394
AN:
248672
AF XY:
0.00199
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.0102
Gnomad EAS exome
AF:
0.0000557
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000196
Gnomad OTH exome
AF:
0.00132
GnomAD4 exome
AF:
0.000749
AC:
1094
AN:
1461406
Hom.:
8
Cov.:
37
AF XY:
0.000981
AC XY:
713
AN XY:
727000
show subpopulations
African (AFR)
AF:
0.0000598
AC:
2
AN:
33454
American (AMR)
AF:
0.0000224
AC:
1
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.0102
AC:
266
AN:
26128
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39692
South Asian (SAS)
AF:
0.00734
AC:
633
AN:
86248
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53394
Middle Eastern (MID)
AF:
0.000867
AC:
5
AN:
5764
European-Non Finnish (NFE)
AF:
0.0000999
AC:
111
AN:
1111658
Other (OTH)
AF:
0.00124
AC:
75
AN:
60350
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.476
Heterozygous variant carriers
0
84
169
253
338
422
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:
0.000506
AC:
77
AN:
152206
Hom.:
0
Cov.:
33
AF XY:
0.000591
AC XY:
44
AN XY:
74398
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41540
American (AMR)
AF:
0.000131
AC:
2
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00980
AC:
34
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5172
South Asian (SAS)
AF:
0.00664
AC:
32
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00340
AC:
1
AN:
294
European-Non Finnish (NFE)
AF:
0.000103
AC:
7
AN:
67992
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.499
Heterozygous variant carriers
0
5
10
16
21
26
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:
0.000853
Hom.:
1
Bravo
AF:
0.000336
Asia WGS
AF:
0.00289
AC:
10
AN:
3478
EpiCase
AF:
0.000218
EpiControl
AF:
0.000178

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:17
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Benign:7
Mar 11, 2015
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

p.Val24189Val in exon 275 of TTN: This variant is not expected to have clinical significance because it has been identified in 0.9% (145/16512) of South Asian c hromosomes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute .org). -

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

- -

Nov 21, 2021
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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

- -

Oct 06, 2023
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 23, 2014
Eurofins Ntd Llc (ga)
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 08, 2015
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:3
-
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

- -

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

TTN: BP4, BP7 -

Autosomal recessive limb-girdle muscular dystrophy type 2J Uncertain:1
Jan 13, 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. -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Benign:1
Jan 27, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiomyopathy Benign:1
Dec 08, 2017
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dilated cardiomyopathy 1G Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Likely 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 likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Early-onset myopathy with fatal cardiomyopathy Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Likely 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 likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Myopathy, myofibrillar, 9, with early respiratory failure Benign:1
Jan 13, 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. -

Tibial muscular dystrophy Benign:1
Jan 13, 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. -

Cardiovascular phenotype Benign:1
Dec 06, 2012
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: 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
BayesDel_noAF
Benign
-0.77
CADD
Benign
0.055
DANN
Benign
0.66
PhyloP100
-0.13
Mutation Taster
=90/10
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: rs199875474; hg19: chr2-179430588; COSMIC: COSV60409556; API