2-178663650-T-A

Position:

chr2-178663650-T-A

Variant summary

Our verdict is Benign. Variant got -19 ACMG points: 1P and 20B. PP2BP4_StrongBP6_Very_StrongBS1BS2

The NM_001267550.2(TTN):c.36509A>T(p.Glu12170Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00284 in 1,613,690 control chromosomes in the GnomAD database, including 10 homozygotes. In-silico tool predicts a benign outcome for this variant. 10/13 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E12170K) has been classified as Benign.

Frequency

Genomes: 𝑓 0.0021 ( 1 hom., cov: 30)

Exomes 𝑓: 0.0029 ( 9 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:15

Conservation

PhyloP100: 1.59

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 (HGNC:):

TTN links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -19 ACMG points.

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), TTN. . Gene score misZ -1.1021 (greater than the threshold 3.09). Trascript score misZ 6.9794 (greater than threshold 3.09). GenCC has associacion of gene with dilated cardiomyopathy, tibial muscular dystrophy, early-onset myopathy with fatal cardiomyopathy, autosomal recessive centronuclear myopathy, hypertrophic cardiomyopathy, hypertrophic cardiomyopathy 9, TTN-related myopathy, dilated cardiomyopathy 1G, arrhythmogenic right ventricular cardiomyopathy, myopathy, myofibrillar, 9, with early respiratory failure, familial isolated dilated cardiomyopathy, childhood-onset progressive contractures-limb-girdle weakness-muscle dystrophy syndrome, autosomal recessive limb-girdle muscular dystrophy type 2J.

BP4

Computational evidence support a benign effect (MetaRNN=0.0069047213).

BP6

Variant 2-178663650-T-A is Benign according to our data. Variant chr2-178663650-T-A is described in ClinVar as [Likely_benign]. Clinvar id is 192173.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-178663650-T-A is described in Lovd as [Benign]. Variant chr2-178663650-T-A is described in Lovd as [Likely_benign].

BS1

Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00214 (326/152230) while in subpopulation NFE AF= 0.00373 (254/68008). AF 95% confidence interval is 0.00336. There are 1 homozygotes in gnomad4. There are 158 alleles in male gnomad4 subpopulation. Median coverage is 30. This position pass quality control queck.

BS2

High Homozygotes in GnomAdExome4 at 9 AD,AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TTN	NM_001267550.2 linkuse as main transcript	c.36509A>T	p.Glu12170Val	missense_variant	171/363	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.36509A>T	p.Glu12170Val	missense_variant	171/363	5	NM_001267550.2	ENSP00000467141.1		A0A0A0MTS7

Frequencies

GnomAD3 genomes

AF:

0.00214

AC:

326

AN:

152116

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000386

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000459

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00442

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00373

Gnomad OTH

AF:

0.000956

GnomAD3 exomes

AF:

0.00228

AC:

563

AN:

247448

Hom.:

AF XY:

0.00233

AC XY:

314

AN XY:

134664

show subpopulations

Gnomad AFR exome

AF:

0.000202

Gnomad AMR exome

AF:

0.000521

Gnomad ASJ exome

AF:

0.000600

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000654

Gnomad FIN exome

AF:

0.00608

Gnomad NFE exome

AF:

0.00347

Gnomad OTH exome

AF:

0.00249

GnomAD4 exome

AF:

0.00292

AC:

4264

AN:

1461460

Hom.:

Cov.:

AF XY:

0.00294

AC XY:

2136

AN XY:

727014

show subpopulations

Gnomad4 AFR exome

AF:

0.000179

Gnomad4 AMR exome

AF:

0.000627

Gnomad4 ASJ exome

AF:

0.000613

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000464

Gnomad4 FIN exome

AF:

0.00680

Gnomad4 NFE exome

AF:

0.00335

Gnomad4 OTH exome

AF:

0.00192

GnomAD4 genome

AF:

0.00214

AC:

326

AN:

152230

Hom.:

Cov.:

AF XY:

0.00212

AC XY:

158

AN XY:

74430

show subpopulations

Gnomad4 AFR

AF:

0.000385

Gnomad4 AMR

AF:

0.000458

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00442

Gnomad4 NFE

AF:

0.00373

Gnomad4 OTH

AF:

0.000948

Alfa

AF:

0.00286

Hom.:

Bravo

AF:

0.00164

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.00377

AC:

ExAC

AF:

0.00229

AC:

276

EpiCase

AF:

0.00267

EpiControl

AF:

0.00279

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:15

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Benign:6

Likely benign, criteria provided, single submitter	research	Biesecker Lab/Clinical Genomics Section, National Institutes of Health	Jun 24, 2013	- -
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, no assertion criteria provided	clinical testing	Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)	-	- -
Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	May 01, 2024	TTN: BP4, BS1 -
Likely benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Oct 26, 2023	- -

not specified

Benign:3

Benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	May 04, 2017	- -
Benign, no assertion criteria provided	clinical testing	Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+	-	- -
Benign, no assertion criteria provided	clinical testing	Clinical Genetics, Academic Medical Center	-	- -

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, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Jun 03, 2019

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

Labcorp Genetics (formerly Invitae), Labcorp

Jan 31, 2024

- -

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

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Benign

-0.43

BayesDel_noAF

Benign

-0.38

CADD

Benign

DANN

Uncertain

0.99

Eigen

Benign

-0.20

Eigen_PC

Benign

-0.22

FATHMM_MKL

Benign

0.37

LIST_S2

Benign

0.31

M_CAP

Benign

0.078

MetaRNN

Benign

0.0069

MetaSVM

Benign

-0.82

Vest4

0.25

MVP

0.64

ClinPred

0.023

GERP RS

3.8

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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