rs34706803

Variant summary

Our verdict is Benign. Variant got -15 ACMG points: 1P and 16B. PP2BP4_StrongBP6_Very_StrongBS2

The NM_001267550.2(TTN):c.13976A>G(p.Tyr4659Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000809 in 1,608,126 control chromosomes in the GnomAD database, including 12 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. Y4659Y) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00079 ( 2 hom., cov: 32)

Exomes 𝑓: 0.00081 ( 10 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:18

Conservation

PhyloP100: 8.02

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:

LOC124906101 (HGNC:):

LOC124906101 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -15 ACMG points.

PP2

Missense variant where missense usually causes diseases, TTN

BP4

Computational evidence support a benign effect (MetaRNN=0.0087429285).

BP6

Variant 2-178739257-T-C is Benign according to our data. Variant chr2-178739257-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 166228.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-178739257-T-C is described in Lovd as [Likely_benign]. Variant chr2-178739257-T-C is described in Lovd as [Benign].

BS2

High Homozygotes in GnomAd at 2 AD,AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTN	NM_001267550.2 linkuse as main transcript	c.13976A>G	p.Tyr4659Cys	missense_variant	48/363	ENST00000589042.5
LOC124906101	XR_007087319.1 linkuse as main transcript			downstream_gene_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTN	ENST00000589042.5 linkuse as main transcript	c.13976A>G	p.Tyr4659Cys	missense_variant	48/363	5	NM_001267550.2	P1
TTN-AS1	ENST00000659121.1 linkuse as main transcript	n.1133+964T>C		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes

AF:

0.000788

AC:

120

AN:

152226

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

Gnomad ASJ

AF:

0.0276

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000265

Gnomad OTH

AF:

0.00143

GnomAD3 exomes

AF:

0.00145

AC:

358

AN:

246586

Hom.:

AF XY:

0.00146

AC XY:

195

AN XY:

133748

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.0318

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000295

Gnomad OTH exome

AF:

0.00185

GnomAD4 exome

AF:

0.000811

AC:

1181

AN:

1455900

Hom.:

Cov.:

AF XY:

0.000837

AC XY:

605

AN XY:

723196

show subpopulations

Gnomad4 AFR exome

AF:

0.0000300

Gnomad4 AMR exome

AF:

0.0000225

Gnomad4 ASJ exome

AF:

0.0343

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.000135

Gnomad4 OTH exome

AF:

0.00233

GnomAD4 genome

AF:

0.000788

AC:

120

AN:

152226

Hom.:

Cov.:

AF XY:

0.000740

AC XY:

AN XY:

74358

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.0276

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000265

Gnomad4 OTH

AF:

0.00143

Alfa

AF:

0.00165

Hom.:

Bravo

AF:

0.000846

TwinsUK

AF:

0.00162

AC:

ALSPAC

AF:

0.000519

AC:

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.00133

AC:

ExAC

AF:

0.00117

AC:

141

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:18

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:6

Benign, no assertion criteria provided	clinical testing	Clinical Genetics, Academic Medical Center	-	- -
Likely benign, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	May 10, 2019	proposed classification - variant undergoing re-assessment, contact laboratory -
Benign, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Jan 06, 2017	- -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Jul 24, 2017	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. -
Benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	Dec 01, 2020	- -
Benign, criteria provided, single submitter	research	Biesecker Lab/Clinical Genomics Section, National Institutes of Health	Jun 24, 2013	- -

not provided

Benign:3

Likely benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -
Likely benign, no assertion criteria provided	clinical testing	Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen	-	- -
Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Mar 01, 2024	TTN: BS1 -

Autosomal recessive limb-girdle muscular dystrophy type 2J

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Sep 10, 2021

- -

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

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jan 31, 2024

- -

Cardiomyopathy

Benign:1

Benign, criteria provided, single submitter

clinical testing

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

May 02, 2018

- -

Early-onset myopathy with fatal cardiomyopathy

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Sep 10, 2021

- -

Tibial muscular dystrophy

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Sep 10, 2021

- -

Myopathy, myofibrillar, 9, with early respiratory failure

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Sep 10, 2021

- -

TTN-related condition

Benign:1

Benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Mar 14, 2019

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Primary dilated cardiomyopathy

Benign:1

Benign, criteria provided, single submitter

clinical testing

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

Apr 06, 2018

- -

Cardiovascular phenotype

Benign:1

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 22, 2018

This alteration is classified as 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

AlphaMissense

Benign

0.25

BayesDel_addAF

Benign

-0.37

BayesDel_noAF

Benign

-0.33

Cadd

Benign

Dann

Benign

0.75

Eigen

Uncertain

0.56

Eigen_PC

Uncertain

0.51

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.86

D;D;.;D;D;D

M_CAP

Benign

0.028

MetaRNN

Benign

0.0087

T;T;T;T;T;T

MetaSVM

Benign

-0.58

MutationTaster

Benign

0.88

D;D;D;D;D;D

PrimateAI

Uncertain

0.63

PROVEAN

Uncertain

-3.9

D;.;.;D;D;.

REVEL

Uncertain

0.51

Sift

Benign

0.17

T;.;.;T;T;.

Vest4

0.82

MVP

0.43

MPC

0.51

ClinPred

0.12

GERP RS

5.8

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