rs191066933

Variant summary

Our verdict is Benign. Variant got -17 ACMG points: 0P and 17B. BP4_StrongBP6_Very_StrongBP7BS1

The NM_001267550.2(TTN):c.58869A>G(p.Lys19623=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000208 in 1,613,378 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0012 ( 1 hom., cov: 33)

Exomes 𝑓: 0.00010 ( 0 hom. )

Consequence

TTN
NM_001267550.2 synonymous

Scores

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:14

Conservation

PhyloP100: 1.52

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 -17 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.54).

BP6

Variant 2-178593339-T-C is Benign according to our data. Variant chr2-178593339-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 47140.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BP7

Synonymous conserved (PhyloP=1.52 with no splicing effect.

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.0012 (183/152158) while in subpopulation AFR AF= 0.00424 (176/41548). AF 95% confidence interval is 0.00372. There are 1 homozygotes in gnomad4. There are 85 alleles in male gnomad4 subpopulation. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTN	NM_001267550.2 linkuse as main transcript	c.58869A>G	p.Lys19623=	synonymous_variant	299/363	ENST00000589042.5
TTN-AS1	NR_038272.1 linkuse as main transcript	n.3364+2025T>C		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.58869A>G	p.Lys19623=	synonymous_variant	299/363	5	NM_001267550.2	P1
TTN-AS1	ENST00000659121.1 linkuse as main transcript	n.417-4257T>C		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes

AF:

0.00120

AC:

182

AN:

152040

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00422

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000328

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.000957

GnomAD3 exomes

AF:

0.000225

AC:

AN:

248790

Hom.:

AF XY:

0.000111

AC XY:

AN XY:

134986

show subpopulations

Gnomad AFR exome

AF:

0.00291

Gnomad AMR exome

AF:

0.000203

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:

0.00000887

Gnomad OTH exome

AF:

0.000497

GnomAD4 exome

AF:

0.000104

AC:

152

AN:

1461220

Hom.:

Cov.:

AF XY:

0.0000853

AC XY:

AN XY:

726884

show subpopulations

Gnomad4 AFR exome

AF:

0.00347

Gnomad4 AMR exome

AF:

0.000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.000398

GnomAD4 genome

AF:

0.00120

AC:

183

AN:

152158

Hom.:

Cov.:

AF XY:

0.00114

AC XY:

AN XY:

74366

show subpopulations

Gnomad4 AFR

AF:

0.00424

Gnomad4 AMR

AF:

0.000327

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000947

Alfa

AF:

0.000392

Hom.:

Bravo

AF:

0.00130

Asia WGS

AF:

0.000577

AC:

AN:

3478

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:14

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:3

Benign, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Mar 19, 2012	p.Lys17055Lys in Exon 248 of TTN: This variant is not expected to have clinical significance because it does not alter an amino acid residue, is not located wit hin the splice consensus sequence and has been identified in 0.4% (11/3044) of A frican American chromosomes from a broad population by the NHLBI Exome Sequencin g Project (http://evs.gs.washington.edu/EVS;). -
Likely benign, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Jun 17, 2016	- -
Likely benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Sep 24, 2020	- -

not provided

Benign:3

Likely benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Aug 23, 2020	- -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Mar 03, 2015	- -
Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Jul 01, 2023	TTN: BP4, BP7 -

Autosomal recessive limb-girdle muscular dystrophy type 2J

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Sep 10, 2021

- -

TTN-related disorder

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Jan 30, 2020

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

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

Mar 16, 2017

- -

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

- -

Cardiovascular phenotype

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 05, 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

-0.54

Cadd

Benign

1.2

Dann

Benign

0.79

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