rs377169251

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 1P and 2B. PP2BP4_Moderate

The NM_001267550.2(TTN):c.53915G>A(p.Arg17972Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000106 in 1,600,274 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/18 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. R17972R) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 4.82

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 Likely_benign. Variant got -1 ACMG points.

PP2

Missense variant where missense usually causes diseases, TTN

BP4

Computational evidence support a benign effect (MetaRNN=0.19465744).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTN	NM_001267550.2 linkuse as main transcript	c.53915G>A	p.Arg17972Gln	missense_variant	280/363	ENST00000589042.5
TTN-AS1	NR_038272.1 linkuse as main transcript	n.4449C>T		non_coding_transcript_exon_variant	17/17

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTN	ENST00000589042.5 linkuse as main transcript	c.53915G>A	p.Arg17972Gln	missense_variant	280/363	5	NM_001267550.2	P1
TTN-AS1	ENST00000659121.1 linkuse as main transcript	n.502+7581C>T		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

151776

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000484

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:

0.00

GnomAD3 exomes

AF:

0.0000127

AC:

AN:

236552

Hom.:

AF XY:

0.00

AC XY:

AN XY:

128384

show subpopulations

Gnomad AFR exome

AF:

0.0000669

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000116

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000104

AC:

AN:

1448498

Hom.:

Cov.:

AF XY:

0.00000973

AC XY:

AN XY:

719480

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000510

Gnomad4 SAS exome

AF:

0.0000356

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000814

Gnomad4 OTH exome

AF:

0.0000167

GnomAD4 genome

AF:

0.0000132

AC:

AN:

151776

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74078

show subpopulations

Gnomad4 AFR

AF:

0.0000484

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:

0.00

Bravo

AF:

0.0000189

ESP6500AA

AF:

0.000265

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000249

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Nov 14, 2019	Not observed at a significant frequency in large population cohorts (Lek et al., 2016); Missense variant in a gene in which most reported pathogenic variants are truncating/loss-of-function; Has not been previously published as pathogenic or benign to our knowledge -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Sep 14, 2018	- -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jan 23, 2013

The Arg15404Gln variant in TTN has not been reported in the literature nor previ ously identified by our laboratory. This variant has been identified in 1/3770 A frican American chromosomes from a broad population by the NHLBI Exome Sequencin g Project (http://evs.gs.washington.edu/EVS). Computational analyses (biochemica l amino acid properties, conservation, AlignGVGD, PolyPhen2, and SIFT) do not pr ovide strong support for or against an impact to the protein. Additional informa tion is needed to fully assess the clinical significance of this variant. -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 29, 2013

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

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.18

BayesDel_addAF

Benign

-0.23

BayesDel_noAF

Benign

-0.34

Cadd

Benign

Dann

Benign

0.97

Eigen

Uncertain

0.57

Eigen_PC

Uncertain

0.64

FATHMM_MKL

Uncertain

0.88

LIST_S2

Uncertain

0.93

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

M_CAP

Benign

0.040

MetaRNN

Benign

0.19

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

MetaSVM

Benign

-0.54

MutationTaster

Benign

1.0

D;D;D;D;D;D

PrimateAI

Benign

0.44

PROVEAN

Uncertain

-2.6

D;N;.;.;N;N;.

REVEL

Benign

0.27

Sift

Benign

0.15

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

Polyphen

0.98

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

Vest4

0.41

MVP

0.26

MPC

0.36

ClinPred

0.29

GERP RS

5.7

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