NM_001267550.2:c.101212C>T

Variant names:

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_001267550.2(TTN):c.101212C>T(p.Arg33738Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00867 in 1,613,814 control chromosomes in the GnomAD database, including 86 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 0.0060 ( 4 hom., cov: 33)

Exomes 𝑓: 0.0089 ( 82 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:24

Conservation

PhyloP100: 7.97

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 links:

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]

TTN-AS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -13 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.008329332).

BP6

Variant 2-178535403-G-A is Benign according to our data. Variant chr2-178535403-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 47633.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=8, Benign=10, Uncertain_significance=1}. Variant chr2-178535403-G-A is described in Lovd as [Benign]. Variant chr2-178535403-G-A is described in Lovd as [Likely_benign]. Variant chr2-178535403-G-A is described in Lovd as [Likely_pathogenic].

BS1

Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00598 (911/152246) while in subpopulation NFE AF= 0.01 (680/68020). AF 95% confidence interval is 0.00937. There are 4 homozygotes in gnomad4. There are 412 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.

BS2

High Homozygotes in GnomAd4 at 4 AD,AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TTN	NM_001267550.2 link	c.101212C>T	p.Arg33738Cys	missense_variant	Exon 358 of 363	ENST00000589042.5	NP_001254479.2	A0A0A0MTS7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TTN	ENST00000589042.5 link	c.101212C>T	p.Arg33738Cys	missense_variant	Exon 358 of 363	5	NM_001267550.2	ENSP00000467141.1		A0A0A0MTS7

Frequencies

GnomAD3 genomes

AF:

0.00599

AC:

912

AN:

152128

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00155

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00537

Gnomad ASJ

AF:

0.00259

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00228

Gnomad FIN

AF:

0.00510

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0100

Gnomad OTH

AF:

0.00525

GnomAD3 exomes

AF:

0.00562

AC:

1399

AN:

248932

Hom.:

AF XY:

0.00561

AC XY:

757

AN XY:

135052

show subpopulations

Gnomad AFR exome

AF:

0.00129

Gnomad AMR exome

AF:

0.00397

Gnomad ASJ exome

AF:

0.00447

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00252

Gnomad FIN exome

AF:

0.00418

Gnomad NFE exome

AF:

0.00866

Gnomad OTH exome

AF:

0.00895

GnomAD4 exome

AF:

0.00895

AC:

13077

AN:

1461568

Hom.:

Cov.:

AF XY:

0.00878

AC XY:

6385

AN XY:

727082

show subpopulations

Gnomad4 AFR exome

AF:

0.00176

Gnomad4 AMR exome

AF:

0.00436

Gnomad4 ASJ exome

AF:

0.00409

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00262

Gnomad4 FIN exome

AF:

0.00493

Gnomad4 NFE exome

AF:

0.0105

Gnomad4 OTH exome

AF:

0.00840

GnomAD4 genome

AF:

0.00598

AC:

911

AN:

152246

Hom.:

Cov.:

AF XY:

0.00553

AC XY:

412

AN XY:

74440

show subpopulations

Gnomad4 AFR

AF:

0.00154

Gnomad4 AMR

AF:

0.00536

Gnomad4 ASJ

AF:

0.00259

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00228

Gnomad4 FIN

AF:

0.00510

Gnomad4 NFE

AF:

0.0100

Gnomad4 OTH

AF:

0.00520

Alfa

AF:

0.00775

Hom.:

Bravo

AF:

0.00579

TwinsUK

AF:

0.00971

AC:

ALSPAC

AF:

0.00986

AC:

ESP6500AA

AF:

0.00230

AC:

ESP6500EA

AF:

0.00976

AC:

ExAC

AF:

0.00563

AC:

681

Asia WGS

AF:

0.00202

AC:

AN:

3478

EpiCase

AF:

0.00834

EpiControl

AF:

0.00907

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:24

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not specified

Benign:8

Oct 17, 2019

Athena Diagnostics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

PreventionGenetics, part of Exact Sciences

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 24, 2015

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

p.Arg31170Cys in exon 307 of TTN: This variant is not expected to have clinical significance because it has been identified in 0.8% (522/66702) of European chro mosomes, including 2 homozygotes, by the Exome Aggregation Consortium (ExAC, htt p://exac.broadinstitute.org; dbSNP rs56273463). -

Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Nov 06, 2019

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: TTN c.93508C>T (p.Arg31170Cys) results in a non-conservative amino acid change located in the M-band region of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.0056 in 248932 control chromosomes, predominantly at a frequency of 0.0087 within the Non-Finnish European subpopulation in the gnomAD database, including 6 homozygotes. The observed variant frequency within Non-Finnish European control individuals in the gnomAD database is approximately 14 fold of the estimated maximal expected allele frequency for a pathogenic variant in TTN causing Cardiomyopathy phenotype (0.00063), strongly suggesting that the variant is a benign polymorphism found primarily in populations of Non-Finnish European origin. The variant, c.93508C>T, has been reported in the literature in individuals affected with Cardiomyopathy and other cardiac disease phenotypes that are not considered to be associated with the titin related disease spectrum (Pugh_2014, Campuzano_2015). These reports therefore do support the association of the variant with Cardiomyopathy. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Six ClinVar submitters (evaluation after 2014) cite the variant as benign (2x), likely benign (3x) and uncertain significance (1x). Based on the evidence outlined above, the variant was classified as benign. -

Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Clinical Genetics, Academic Medical Center

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Jul 24, 2015

Eurofins Ntd Llc (ga)

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided

Benign:7

Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Feb 10, 2015

Genetic Services Laboratory, University of Chicago

Significance: Likely benign

Review Status: criteria provided, single submitter

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

- -

Aug 22, 2018

GeneDx

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is associated with the following publications: (PMID: 32403337) -

Nov 29, 2023

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Genome Diagnostics Laboratory, University Medical Center Utrecht

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Nov 01, 2024

CeGaT Center for Human Genetics Tuebingen

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

TTN: BS1, BS2 -

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. -

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

Benign:1

Feb 04, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Dilated cardiomyopathy 1G

Benign:1

Jan 12, 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. -

Cardiomyopathy

Benign:1

Nov 09, 2017

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

Jan 12, 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. -

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. -

Cardiovascular phenotype

Benign:1

Dec 10, 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. -

TTN-related myopathy

Benign:1

Jun 06, 2023

Molecular Genetics, Royal Melbourne Hospital

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Atrial fibrillation;C0878544:Cardiomyopathy

Benign:1

Jun 11, 2019

Center for Advanced Laboratory Medicine, UC San Diego Health, University of California San Diego

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.60

BayesDel_addAF

Benign

-0.31

BayesDel_noAF

Benign

-0.21

CADD

Uncertain

DANN

Benign

0.97

Eigen

Pathogenic

0.84

Eigen_PC

Pathogenic

0.82

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.96

D;D;D;.;D;D;D

MetaRNN

Benign

0.0083

T;T;T;T;T;T;T

MetaSVM

Benign

-0.41

MutationAssessor

Uncertain

2.3

.;.;.;M;.;.;M

PrimateAI

Uncertain

0.68

PROVEAN

Pathogenic

-5.8

D;D;.;.;D;D;.

REVEL

Uncertain

0.46

Sift

Benign

0.035

D;T;.;.;T;D;.

Polyphen

1.0

.;.;.;D;.;.;D

Vest4

0.46

MVP

0.72

MPC

0.54

ClinPred

0.029

GERP RS

5.5

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over