rs200103997

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_001267550.2(TTN):​c.24952G>A​(p.Val8318Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000749 in 1,613,726 control chromosomes in the GnomAD database, with no homozygous occurrence. 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00055 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00077 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:13

Conservation

PhyloP100: -0.0820
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 made for transcript

Verdict is Likely_benign. Variant got -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.006938517).
BP6
Variant 2-178718054-C-T is Benign according to our data. Variant chr2-178718054-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 166152.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=5, Benign=3, Uncertain_significance=7}. Variant chr2-178718054-C-T is described in Lovd as [Likely_benign]. Variant chr2-178718054-C-T is described in Lovd as [Benign].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.24952G>A p.Val8318Ile missense_variant Exon 86 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.24952G>A p.Val8318Ile missense_variant Exon 86 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000546
AC:
83
AN:
152134
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000482
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0000943
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00115
Gnomad OTH
AF:
0.000478
GnomAD3 exomes
AF:
0.000587
AC:
146
AN:
248762
Hom.:
0
AF XY:
0.000615
AC XY:
83
AN XY:
134944
show subpopulations
Gnomad AFR exome
AF:
0.000129
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.000279
Gnomad NFE exome
AF:
0.00118
Gnomad OTH exome
AF:
0.000663
GnomAD4 exome
AF:
0.000770
AC:
1125
AN:
1461474
Hom.:
0
Cov.:
35
AF XY:
0.000752
AC XY:
547
AN XY:
727034
show subpopulations
Gnomad4 AFR exome
AF:
0.000149
Gnomad4 AMR exome
AF:
0.000157
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.000244
Gnomad4 NFE exome
AF:
0.000962
Gnomad4 OTH exome
AF:
0.000480
GnomAD4 genome
AF:
0.000552
AC:
84
AN:
152252
Hom.:
0
Cov.:
32
AF XY:
0.000403
AC XY:
30
AN XY:
74442
show subpopulations
Gnomad4 AFR
AF:
0.0000481
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.0000943
Gnomad4 NFE
AF:
0.00116
Gnomad4 OTH
AF:
0.000473
Alfa
AF:
0.000771
Hom.:
1
Bravo
AF:
0.000578
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ESP6500AA
AF:
0.000256
AC:
1
ESP6500EA
AF:
0.000847
AC:
7
ExAC
AF:
0.000736
AC:
89
EpiCase
AF:
0.000764
EpiControl
AF:
0.000771

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:7Benign:13
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3Benign:5
-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Apr 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

TTN: BP4 -

Apr 19, 2021
GeneDx
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

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

-
Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

-
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

- -

May 31, 2018
Eurofins Ntd Llc (ga)
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 29, 2023
Mayo Clinic Laboratories, Mayo Clinic
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

BP4 -

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

- -

not specified Uncertain:1Benign:3
-
Clinical Genetics, Academic Medical Center
Significance: Benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Sep 16, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Feb 12, 2015
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

p.Val7074Ile in exon 83 of TTN: This variant is not expected to have clinical si gnificance due to a lack of conservation across species, including mammals. Of n ote, >10 mammals have an isoleucine (Ile) at this position despite high nearby a mino acid conservation. In addition, computational prediction tools do not sugge st a high likelihood of impact to the protein. This variant has also been identi fied in 0.1% (84/66708) of European chromosomes by the Exome Aggregation Consort ium (ExAC, http://exac.broadinstitute.org; dbSNP rs200103997). -

May 23, 2016
Genetic Services Laboratory, University of Chicago
Significance: Uncertain significance
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
Jan 02, 2024
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
Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Cardiomyopathy Benign:1
Oct 01, 2021
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

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. -

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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.065
BayesDel_addAF
Benign
-0.56
T
BayesDel_noAF
Benign
-0.63
CADD
Benign
7.3
DANN
Benign
0.76
Eigen
Benign
-1.1
Eigen_PC
Benign
-1.0
FATHMM_MKL
Benign
0.060
N
LIST_S2
Benign
0.64
T;T;.;T
M_CAP
Benign
0.016
T
MetaRNN
Benign
0.0069
T;T;T;T
MetaSVM
Benign
-0.96
T
PrimateAI
Benign
0.29
T
PROVEAN
Benign
-0.55
N;.;.;.
REVEL
Benign
0.063
Sift
Benign
0.57
T;.;.;.
Polyphen
0.0080
.;.;B;B
Vest4
0.081
MVP
0.13
MPC
0.069
ClinPred
0.0012
T
GERP RS
1.1

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs200103997; hg19: chr2-179582781; COSMIC: COSV100612863; COSMIC: COSV100612863; API