rs368770038

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 1P and 3B. PP2BP4_ModerateBP6

The NM_001267550.2(TTN):c.3070G>A(p.Val1024Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000254 in 1,613,338 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 11/18 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V1024G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 3.11

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:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PP2

Missense variant where missense usually causes diseases, TTN

BP4

Computational evidence support a benign effect (MetaRNN=0.22959569).

BP6

Variant 2-178782836-C-T is Benign according to our data. Variant chr2-178782836-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 166331.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTN	NM_001267550.2 linkuse as main transcript	c.3070G>A	p.Val1024Ile	missense_variant	18/363	ENST00000589042.5
TTN	NM_133379.5 linkuse as main transcript	c.3070G>A	p.Val1024Ile	missense_variant	18/46	ENST00000360870.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTN	ENST00000589042.5 linkuse as main transcript	c.3070G>A	p.Val1024Ile	missense_variant	18/363	5	NM_001267550.2	P1
TTN	ENST00000360870.10 linkuse as main transcript	c.3070G>A	p.Val1024Ile	missense_variant	18/46	5	NM_133379.5		Q8WZ42-6

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152210

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.000478

GnomAD3 exomes

AF:

0.0000399

AC:

AN:

250612

Hom.:

AF XY:

0.0000443

AC XY:

AN XY:

135440

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000708

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000274

AC:

AN:

1461128

Hom.:

Cov.:

AF XY:

0.0000220

AC XY:

AN XY:

726892

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000351

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152210

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74358

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

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:

0.000478

Alfa

AF:

0.0000966

Hom.:

Bravo

AF:

0.0000227

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000247

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not specified

Uncertain:1Benign:1

Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Aug 22, 2017	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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Jul 11, 2014	Variant classified as Uncertain Significance - Favor Benign. The Val1024Ile vari ant in TTN has not been previously reported in individuals with cardiomyopathy, but has been identified in 1/4406 of African American chromosomes by the NHLBI E xome Sequencing Project (http://evs.gs.washington.edu/EVS/; dbSNP rs368770038). Valine (Val) at position 1024 is conserved in mammals, though several other spec ies (softshell turtle, spiny softshell turtle, tetradon, madaka, southern platyf ish, and zebrafish) have an isoleucine (Ile) at this position, raising the possi bility that this change may be tolerated. Additional computational prediction to ols do not provide strong support for or against an impact to the protein. In su mmary, while the clinical significance of the Val1024Ile variant is uncertain, t he presence of the variant amino acid in other species suggests that it is more likely to be benign. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.12

BayesDel_addAF

Benign

-0.16

BayesDel_noAF

Benign

-0.28

Cadd

Uncertain

Dann

Uncertain

0.97

Eigen

Uncertain

0.31

Eigen_PC

Uncertain

0.41

FATHMM_MKL

Uncertain

0.92

LIST_S2

Uncertain

0.91

D;D;D;.;D;D;D;D

M_CAP

Benign

0.024

MetaRNN

Benign

0.23

T;T;T;T;T;T;T;T

MetaSVM

Benign

-0.63

MutationTaster

Benign

0.75

D;N;N;N;N;N;N

PrimateAI

Uncertain

0.53

PROVEAN

Benign

-0.58

N;N;.;.;N;N;.;N

REVEL

Benign

0.26

Sift

Benign

0.24

T;T;.;.;T;T;.;T

Polyphen

0.77, 0.98

.;.;.;P;.;.;P;D

Vest4

0.32

MVP

0.49

MPC

0.093

ClinPred

0.074

GERP RS

6.2

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