chr2-178745750-A-G

Variant names:

Variant summary

Our verdict is Benign. Variant got -19 ACMG points: 0P and 19B. BP4_ModerateBP6_Very_StrongBP7BS1BS2

The NM_133379.5(TTN):c.16650T>C(p.Asp5550Asp) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00169 in 1,612,774 control chromosomes in the GnomAD database, including 48 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

Frequency

Genomes: 𝑓 0.0090 ( 24 hom., cov: 32)

Exomes 𝑓: 0.00093 ( 24 hom. )

Consequence

TTN
NM_133379.5 synonymous

Scores

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:6

Conservation

PhyloP100: 2.35

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 -19 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.39).

BP6

Variant 2-178745750-A-G is Benign according to our data. Variant chr2-178745750-A-G is described in ClinVar as [Benign]. Clinvar id is 47804.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-178745750-A-G is described in Lovd as [Benign].

BP7

Synonymous conserved (PhyloP=2.35 with no splicing effect.

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.009 (1369/152040) while in subpopulation AFR AF= 0.0312 (1293/41506). AF 95% confidence interval is 0.0297. There are 24 homozygotes in gnomad4. There are 630 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.

BS2

High Homozygotes in GnomAd4 at 24 AD,AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TTN	NM_133379.5 link	c.16650T>C	p.Asp5550Asp	synonymous_variant	Exon 46 of 46	ENST00000360870.10	NP_596870.2	Q8WZ42-6Q7Z3B7
TTN	NM_001267550.2 link	c.11312-3829T>C		intron_variant	Intron 47 of 362	ENST00000589042.5	NP_001254479.2	A0A0A0MTS7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TTN	ENST00000360870.10 link	c.16650T>C	p.Asp5550Asp	synonymous_variant	Exon 46 of 46	5	NM_133379.5	ENSP00000354117.4		Q8WZ42-6
TTN	ENST00000589042.5 link	c.11312-3829T>C		intron_variant	Intron 47 of 362	5	NM_001267550.2	ENSP00000467141.1		A0A0A0MTS7

Frequencies

GnomAD3 genomes

AF:

0.00898

AC:

1364

AN:

151922

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0311

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00250

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00633

Gnomad NFE

AF:

0.000147

Gnomad OTH

AF:

0.0125

GnomAD3 exomes

AF:

0.00228

AC:

568

AN:

249606

Hom.:

AF XY:

0.00171

AC XY:

231

AN XY:

134878

show subpopulations

Gnomad AFR exome

AF:

0.0313

Gnomad AMR exome

AF:

0.00113

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:

0.000133

Gnomad OTH exome

AF:

0.000987

GnomAD4 exome

AF:

0.000929

AC:

1357

AN:

1460734

Hom.:

Cov.:

AF XY:

0.000804

AC XY:

584

AN XY:

726656

show subpopulations

Gnomad4 AFR exome

AF:

0.0336

Gnomad4 AMR exome

AF:

0.00128

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000464

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000261

Gnomad4 OTH exome

AF:

0.00219

GnomAD4 genome

AF:

0.00900

AC:

1369

AN:

152040

Hom.:

Cov.:

AF XY:

0.00847

AC XY:

630

AN XY:

74354

show subpopulations

Gnomad4 AFR

AF:

0.0312

Gnomad4 AMR

AF:

0.00249

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000147

Gnomad4 OTH

AF:

0.0123

Alfa

AF:

0.00509

Hom.:

Bravo

AF:

0.0104

Asia WGS

AF:

0.000866

AC:

AN:

3478

EpiCase

AF:

0.0000546

EpiControl

AF:

0.000178

ClinVar

Significance: Benign

Submissions summary: Benign:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:4

Mar 16, 2012

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Asp5550Asp in exon 45A of TTN: This variant is not expected to have clinical sig nificance because it does not alter an amino acid residue, is not located within the splice consensus sequence, and has been identified in 2.9% (110/3738) of Af rican American chromosomes from a broad population by the NHLBI Exome Sequencing Project (http://evs.gs.washington.edu/EVS; dbSNP rs16866488). -

Nov 07, 2014

GeneDx

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. -

Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Clinical Genetics, Academic Medical Center

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

not provided

Benign:2

Breakthrough Genomics, Breakthrough Genomics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: not provided

- -

Sep 28, 2023

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.39

CADD

Benign

DANN

Benign

0.69

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