NM_001267550.2:c.88123C>T

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_001267550.2(TTN):c.88123C>T(p.Arg29375Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000316 in 1,613,634 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R29375H) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000099 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1

Conservation

PhyloP100: 3.36

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 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:

ENSG00000279598 (HGNC:):

ENSG00000279598 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.24807939).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TTN	NM_001267550.2 link	c.88123C>T	p.Arg29375Cys	missense_variant	Exon 330 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.88123C>T	p.Arg29375Cys	missense_variant	Exon 330 of 363	5	NM_001267550.2	ENSP00000467141.1		A0A0A0MTS7

Frequencies

GnomAD3 genomes

AF:

0.0000986

AC:

AN:

152148

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000655

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000193

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000588

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000805

AC:

AN:

248574

AF XY:

0.0000519

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000290

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000785

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000444

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000246

AC:

AN:

1461486

Hom.:

Cov.:

AF XY:

0.0000206

AC XY:

AN XY:

727032

show subpopulations

African (AFR)

AF:

0.0000299

AC:

AN:

33478

American (AMR)

AF:

0.0000224

AC:

AN:

44722

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26132

East Asian (EAS)

AF:

0.000202

AC:

AN:

39594

South Asian (SAS)

AF:

0.00

AC:

AN:

86248

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53380

Middle Eastern (MID)

AF:

0.000173

AC:

AN:

5766

European-Non Finnish (NFE)

AF:

0.0000207

AC:

AN:

1111802

Other (OTH)

AF:

0.0000331

AC:

AN:

60364

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.482

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.0000986

AC:

AN:

152148

Hom.:

Cov.:

AF XY:

0.000121

AC XY:

AN XY:

74316

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41444

American (AMR)

AF:

0.000655

AC:

AN:

15266

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.000193

AC:

AN:

5194

South Asian (SAS)

AF:

0.00

AC:

AN:

4828

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10594

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000588

AC:

AN:

68030

Other (OTH)

AF:

0.00

AC:

AN:

2092

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.485

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<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:

0.0000386

Hom.:

Bravo

AF:

0.0000680

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000121

AC:

ExAC

AF:

0.0000579

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:4Benign:1

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

Significance:Uncertain significance

Review Status:no assertion criteria provided

Collection Method:clinical testing

- -

Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen

Significance:Uncertain significance

Review Status:no assertion criteria provided

Collection Method:clinical testing

- -

Nov 17, 2020

Revvity Omics, Revvity

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Mar 05, 2021

GeneDx

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Clinical Genetics, Academic Medical Center

Significance:Uncertain significance

Review Status:no assertion criteria provided

Collection Method:clinical testing

- -

not specified

Uncertain:1

Oct 26, 2017

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The p.Arg26807Cys variant in TTN has not been previously reported in individuals with cardiomyopathy. It has been identified in 13/17114 East Asian chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; db SNP rs368439674). Computational prediction tools and conservation analysis do no t provide strong support for or against an impact to the protein. In summary, th e clinical significance of the p.Arg2680Cys variant is uncertain. ACMG/AMP Crit eria applied: none (Richards 2015). -

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

Uncertain:1

Oct 17, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Cardiovascular phenotype

Uncertain:1

Dec 26, 2018

Ambry Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The p.R20310C variant (also known as c.60928C>T), located in coding exon 157 of the TTN gene, results from a C to T substitution at nucleotide position 60928. The arginine at codon 20310 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.27

BayesDel_addAF

Benign

-0.25

BayesDel_noAF

Benign

-0.22

CADD

Benign

(source)

DANN

Benign

0.92

Eigen

Pathogenic

0.69

Eigen_PC

Uncertain

0.65

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.92

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

M_CAP

Benign

0.022

MetaRNN

Benign

0.25

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

MetaSVM

Uncertain

-0.25

MutationAssessor

Uncertain

2.4

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

PhyloP100

3.4

PrimateAI

Uncertain

0.53

PROVEAN

Pathogenic

-5.4

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

REVEL

Uncertain

0.43

Sift

Pathogenic

0.0

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

Polyphen

1.0

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

Vest4

0.43

MVP

0.59

MPC

0.44

ClinPred

0.26

GERP RS

5.9

Mutation Taster

=91/9

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over