rs371656672

Variant summary

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

The NM_001267550.2(TTN):c.99340T>C(p.Leu33114=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00028 in 1,613,242 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).

Frequency

Genomes: 𝑓 0.00015 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00029 ( 0 hom. )

Consequence

TTN
NM_001267550.2 synonymous

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:11

Conservation

PhyloP100: 1.42

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 Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.49).

BP6

Variant 2-178537867-A-G is Benign according to our data. Variant chr2-178537867-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 47616.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=9, Uncertain_significance=1}. Variant chr2-178537867-A-G is described in Lovd as [Likely_benign]. Variant chr2-178537867-A-G is described in Lovd as [Benign].

BP7

Synonymous conserved (PhyloP=1.42 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTN	NM_001267550.2 linkuse as main transcript	c.99340T>C	p.Leu33114=	synonymous_variant	355/363	ENST00000589042.5
TTN-AS1	NR_038272.1 linkuse as main transcript	n.647+176A>G		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTN	ENST00000589042.5 linkuse as main transcript	c.99340T>C	p.Leu33114=	synonymous_variant	355/363	5	NM_001267550.2	P1
TTN-AS1	ENST00000659121.1 linkuse as main transcript	n.416+14231A>G		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes

AF:

0.000151

AC:

AN:

152156

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000415

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000226

AC:

AN:

247980

Hom.:

AF XY:

0.000223

AC XY:

AN XY:

134610

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000174

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.000262

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000374

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000293

AC:

428

AN:

1461086

Hom.:

Cov.:

AF XY:

0.000272

AC XY:

198

AN XY:

726788

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000179

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.000174

Gnomad4 FIN exome

AF:

0.0000187

Gnomad4 NFE exome

AF:

0.000337

Gnomad4 OTH exome

AF:

0.000381

GnomAD4 genome

AF:

0.000151

AC:

AN:

152156

Hom.:

Cov.:

AF XY:

0.000175

AC XY:

AN XY:

74310

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000415

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000198

Hom.:

Bravo

AF:

0.000196

Asia WGS

AF:

0.000289

AC:

AN:

3478

EpiCase

AF:

0.000218

EpiControl

AF:

0.000238

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:11

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not specified

Benign:5

Likely benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	Mar 03, 2021	- -
Likely benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Aug 26, 2023	- -
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	Jul 25, 2012	Leu30546Leu in exon 304 of TTN: This variant is not expected to have clinical si gnificance because it does not alter an amino acid residue and is not located wi thin the splice consensus sequence. It has been identified in 1/8232 European Am erican chromosomes from a broad population by the NHLBI Exome Sequencing Project (http://evs.gs.washington.edu/EVS). Leu30546Leu in exon 304 of TTN (allele fr equency =1/8232) ** -
Likely benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Jan 14, 2019	- -

not provided

Uncertain:1Benign:3

Likely benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -
Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Jan 01, 2024	TTN: BP4, BP7 -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Mar 02, 2016	- -
Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Sep 14, 2020	- -

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

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jan 27, 2024

- -

Cardiomyopathy

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

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

Jun 29, 2022

- -

Cardiovascular phenotype

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 22, 2018

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

-0.49

Cadd

Benign

0.033

Dann

Benign

0.66

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