rs202160275

Positions:

chr2-178709812-C-T

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 1P and 9B. PP2BP4_StrongBP6BS1

The NM_001267550.2(TTN):c.28507G>A(p.Val9503Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000239 in 1,613,380 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/18 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00028 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00023 ( 1 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:7

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:

LOC124906100 (HGNC:):

LOC124906100 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -8 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=0.008672595).

BP6

Variant 2-178709812-C-T is Benign according to our data. Variant chr2-178709812-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 166133.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=3, Benign=4, Uncertain_significance=6}.

BS1

Variant frequency is greater than expected in population mid. gnomad4_exome allele frequency = 0.000235 (343/1461228) while in subpopulation MID AF= 0.00659 (38/5764). AF 95% confidence interval is 0.00494. There are 1 homozygotes in gnomad4_exome. There are 180 alleles in male gnomad4_exome subpopulation. Median coverage is 31. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TTN	NM_001267550.2 linkuse as main transcript	c.28507G>A	p.Val9503Ile	missense_variant	99/363	ENST00000589042.5	NP_001254479.2
LOC124906100	XR_007087318.1 linkuse as main transcript	n.2186-3942C>T		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TTN	ENST00000589042.5 linkuse as main transcript	c.28507G>A	p.Val9503Ile	missense_variant	99/363	5	NM_001267550.2	ENSP00000467141	P1
TTN-AS1	ENST00000659121.1 linkuse as main transcript	n.503-24692C>T		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes

AF:

0.000276

AC:

AN:

152152

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000393

Gnomad ASJ

AF:

0.00461

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000250

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.000382

AC:

AN:

248728

Hom.:

AF XY:

0.000400

AC XY:

AN XY:

134954

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000696

Gnomad ASJ exome

AF:

0.00437

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000654

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000204

Gnomad OTH exome

AF:

0.000331

GnomAD4 exome

AF:

0.000235

AC:

343

AN:

1461228

Hom.:

Cov.:

AF XY:

0.000248

AC XY:

180

AN XY:

726894

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.000559

Gnomad4 ASJ exome

AF:

0.00459

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000464

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.000107

Gnomad4 OTH exome

AF:

0.000596

GnomAD4 genome

AF:

0.000276

AC:

AN:

152152

Hom.:

Cov.:

AF XY:

0.000256

AC XY:

AN XY:

74304

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.000393

Gnomad4 ASJ

AF:

0.00461

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000250

Gnomad4 OTH

AF:

0.000478

Alfa

AF:

0.000503

Hom.:

Bravo

AF:

0.000363

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000245

AC:

ExAC

AF:

0.000364

AC:

EpiCase

AF:

0.000436

EpiControl

AF:

0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:6Benign:7

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:2Benign:1

Uncertain significance, criteria provided, single submitter	research	Biesecker Lab/Clinical Genomics Section, National Institutes of Health	Jun 24, 2013	- -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Apr 05, 2021	This variant is associated with the following publications: (PMID: 23861362) -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Feb 22, 2017	- -

not specified

Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Jul 16, 2014	Val8259Ile in exon 96 of TTN: This variant is not expected to have clinical sign ificance due to a lack of conservation across species, including mammals. Of not e, squirrel, rat, shrew, aardvark and multiple lower species have an isoleucine (Ile) at this position despite high nearby amino acid conservation. It has also been identified in 2/8158 European American chromosomes by the NHLBI Exome Seque ncing Project (http://evs.gs.washington.edu/EVS/; dbSNP rs202160275). -
Likely benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	Nov 17, 2016	- -

Autosomal recessive limb-girdle muscular dystrophy type 2J

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Dilated cardiomyopathy 1G

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

Early-onset myopathy with fatal cardiomyopathy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 10, 2013

There is insufficient or conflicting evidence for classification of this alteration. -

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

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 31, 2024

- -

Cardiomyopathy

Benign:1

Benign, criteria provided, single submitter

clinical testing

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

Jun 19, 2018

- -

Tibial muscular dystrophy

Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Myopathy, myofibrillar, 9, with early respiratory failure

Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.069

BayesDel_addAF

Benign

-0.44

BayesDel_noAF

Benign

-0.50

CADD

Benign

DANN

Benign

0.94

Eigen

Benign

-0.27

Eigen_PC

Benign

-0.12

FATHMM_MKL

Uncertain

0.78

LIST_S2

Benign

0.68

T;T;.;T

M_CAP

Benign

0.013

MetaRNN

Benign

0.0087

T;T;T;T

MetaSVM

Benign

-0.86

MutationTaster

Benign

1.0

D;D;D;N;N;N

PrimateAI

Benign

0.31

PROVEAN

Benign

-0.38

N;.;.;.

REVEL

Benign

0.12

Sift

Benign

0.35

T;.;.;.

Polyphen

0.0010

.;.;B;B

Vest4

0.091

MVP

0.46

MPC

0.069

ClinPred

0.022

GERP RS

3.1

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