rs371444691

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_133379.5(TTN):c.14902G>A(p.Asp4968Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000132 in 1,613,392 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. 10/14 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 0.000039 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00014 ( 2 hom. )

Consequence

TTN
NM_133379.5 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 7.48

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 -5 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.016041756).

BP6

Variant 2-178747498-C-T is Benign according to our data. Variant chr2-178747498-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 47779.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=1}. Variant chr2-178747498-C-T is described in Lovd as [Benign].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTN	NM_133379.5 linkuse as main transcript	c.14902G>A	p.Asp4968Asn	missense_variant	46/46	ENST00000360870.10
TTN	NM_001267550.2 linkuse as main transcript	c.11312-5577G>A		intron_variant		ENST00000589042.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTN	ENST00000360870.10 linkuse as main transcript	c.14902G>A	p.Asp4968Asn	missense_variant	46/46	5	NM_133379.5		Q8WZ42-6
TTN	ENST00000589042.5 linkuse as main transcript	c.11312-5577G>A		intron_variant		5	NM_001267550.2	P1
TTN-AS1	ENST00000659121.1 linkuse as main transcript	n.1223+4528C>T		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes

AF:

0.0000461

AC:

AN:

151960

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00124

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000267

AC:

AN:

250554

Hom.:

AF XY:

0.000391

AC XY:

AN XY:

135386

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00216

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.000164

GnomAD4 exome

AF:

0.000142

AC:

207

AN:

1461314

Hom.:

Cov.:

AF XY:

0.000213

AC XY:

155

AN XY:

726956

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:

0.00228

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

9.00e-7

Gnomad4 OTH exome

AF:

0.000149

GnomAD4 genome

AF:

0.0000395

AC:

AN:

152078

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74340

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00104

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000680

Hom.:

Bravo

AF:

0.0000189

ExAC

AF:

0.000305

AC:

Asia WGS

AF:

0.00115

AC:

AN:

3478

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Nov 20, 2012

The Asp4968Asn variant in TTN has not been reported in the literature, but has b een identified in two Asian individuals with cardiomyopathy tested by our labora tory. Computational analyses are limited or unavailable for this variant. Additi onal data is needed to determine its clinical significance. -

not provided

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

CeGaT Center for Human Genetics Tuebingen

Dec 01, 2023

TTN: BP4, BS2 -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Benign

-0.45

BayesDel_noAF

Benign

-0.42

Cadd

Benign

Dann

Uncertain

1.0

Eigen

Benign

0.025

Eigen_PC

Benign

0.16

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.68

M_CAP

Benign

0.014

MetaRNN

Benign

0.016

MetaSVM

Benign

-0.86

MutationTaster

Benign

1.0

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

PROVEAN

Benign

-0.99

REVEL

Benign

0.11

Sift

Uncertain

0.010

Sift4G

Uncertain

0.050

Polyphen

0.026

Vest4

0.29

MutPred

0.23

Loss of sheet (P = 0.1158);

MVP

0.53

ClinPred

0.14

GERP RS

4.9

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