rs200717463

Positions:

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_StrongBP6BP7

The NM_001256850.1(TTN):c.63900C>T(p.Tyr21300Tyr) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000923 in 1,602,660 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00016 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000085 ( 0 hom. )

Consequence

TTN
NM_001256850.1 splice_region, synonymous

Scores

Splicing: ADA: 0.0004091

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:4

Conservation

PhyloP100: 0.226

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:):

TTN-AS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.56).

BP6

Variant 2-178577603-G-A is Benign according to our data. Variant chr2-178577603-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 229502.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=3, Uncertain_significance=1}.

BP7

Synonymous conserved (PhyloP=0.226 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TTN	NM_001267550.2 linkuse as main transcript	c.68823C>T	p.Tyr22941Tyr	synonymous_variant	323/363	ENST00000589042.5	NP_001254479.2	A0A0A0MTS7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TTN	ENST00000589042.5 linkuse as main transcript	c.68823C>T	p.Tyr22941Tyr	synonymous_variant	323/363	5	NM_001267550.2	ENSP00000467141.1		A0A0A0MTS7

Frequencies

GnomAD3 genomes

AF:

0.000151

AC:

AN:

151966

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000217

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000590

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000194

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000441

Gnomad OTH

AF:

0.000479

GnomAD3 exomes

AF:

0.0000498

AC:

AN:

240894

Hom.:

AF XY:

0.0000460

AC XY:

AN XY:

130418

show subpopulations

Gnomad AFR exome

AF:

0.0000651

Gnomad AMR exome

AF:

0.000239

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000182

Gnomad OTH exome

AF:

0.000171

GnomAD4 exome

AF:

0.0000855

AC:

124

AN:

1450576

Hom.:

Cov.:

AF XY:

0.0000833

AC XY:

AN XY:

720358

show subpopulations

Gnomad4 AFR exome

AF:

0.000212

Gnomad4 AMR exome

AF:

0.000207

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000507

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000378

Gnomad4 NFE exome

AF:

0.0000895

Gnomad4 OTH exome

AF:

0.0000834

GnomAD4 genome

AF:

0.000158

AC:

AN:

152084

Hom.:

Cov.:

AF XY:

0.000161

AC XY:

AN XY:

74332

show subpopulations

Gnomad4 AFR

AF:

0.000241

Gnomad4 AMR

AF:

0.000589

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000194

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.000474

Alfa

AF:

0.0000817

Hom.:

Bravo

AF:

0.000170

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:4

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jan 29, 2015

Variant classified as Uncertain Significance - Favor Benign. The p.Tyr20373Tyr v ariant in TTN has not been previously reported in individuals with cardiomyopath y, but has been identified in 3/115068 chromosomes from several populations by t he Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs2 00717463). Although this variant does not alter an amino acid residue, this vari ant is located in the last three bases of the exon, which is part of the 5? spli ce region. Computational tools do not suggest an impact to splicing. However, th is information is not predictive enough to rule out pathogenicity. In summary, w hile the clinical significance of the p.Tyr20373Tyr variant is uncertain, the fa ct that it does not alter an amino acid residue and that it is not predicted to alter splicing suggests that it is more likely to be benign. -

TTN-related disorder

Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Feb 18, 2023

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

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 29, 2024

- -

not provided

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Feb 24, 2021

- -

Cardiovascular phenotype

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 30, 2019

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, 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

-0.56

CADD

Benign

2.6

DANN

Benign

0.44

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.00041

dbscSNV1_RF

Benign

0.076

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