rs777009984

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_001267550.2(TTN):​c.6420T>A​(p.Asp2140Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000353 in 1,613,936 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).

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000033 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

7
10

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1

Conservation

PhyloP100: 2.69
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-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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.23795038).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.6420T>A p.Asp2140Glu missense_variant Exon 28 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7
TTNNM_133379.5 linkc.6420T>A p.Asp2140Glu missense_variant Exon 28 of 46 ENST00000360870.10 NP_596870.2 Q8WZ42-6Q7Z3B7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.6420T>A p.Asp2140Glu missense_variant Exon 28 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7
TTNENST00000360870.10 linkc.6420T>A p.Asp2140Glu missense_variant Exon 28 of 46 5 NM_133379.5 ENSP00000354117.4 Q8WZ42-6

Frequencies

GnomAD3 genomes
AF:
0.0000591
AC:
9
AN:
152164
Hom.:
0
Cov.:
32
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:
0.000132
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000598
AC:
15
AN:
251044
Hom.:
0
AF XY:
0.0000516
AC XY:
7
AN XY:
135660
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:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000123
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000328
AC:
48
AN:
1461772
Hom.:
0
Cov.:
33
AF XY:
0.0000330
AC XY:
24
AN XY:
727184
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:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000423
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000591
AC:
9
AN:
152164
Hom.:
0
Cov.:
32
AF XY:
0.0000673
AC XY:
5
AN XY:
74348
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:
0.000132
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000113
Hom.:
0
Bravo
AF:
0.0000642
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:7Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:5Benign:1
Dec 06, 2018
GeneDx
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 21, 2024
Mayo Clinic Laboratories, Mayo Clinic
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

-
Clinical Genetics, Academic Medical Center
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

not specified Uncertain:1
Apr 14, 2015
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.Asp2140Glu variant in TTN has not been previously reported in individuals with cardiomyopathy, but has been identified in 4/66660 European chromosomes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org). Computa tional prediction tools and conservation analysis do not provide strong support for or against an impact to the protein. In summary, the clinical significance o f the p.Asp2140Glu variant is uncertain. -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Jul 06, 2016
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.23
BayesDel_addAF
Benign
-0.18
T
BayesDel_noAF
Benign
-0.25
CADD
Benign
16
DANN
Benign
0.81
Eigen
Uncertain
0.20
Eigen_PC
Benign
0.17
FATHMM_MKL
Uncertain
0.83
D
LIST_S2
Uncertain
0.90
D;D;D;.;D;D;T;D
M_CAP
Benign
0.018
T
MetaRNN
Benign
0.24
T;T;T;T;T;T;T;T
MetaSVM
Benign
-0.55
T
PrimateAI
Uncertain
0.77
T
PROVEAN
Uncertain
-2.5
D;D;.;.;D;D;.;D
REVEL
Uncertain
0.40
Sift
Benign
0.31
T;T;.;.;T;T;.;T
Sift4G
Uncertain
0.0040
.;.;.;.;.;.;.;D
Polyphen
1.0
.;.;.;D;.;.;D;D
Vest4
0.32
MutPred
0.57
Gain of disorder (P = 0.1658);.;Gain of disorder (P = 0.1658);Gain of disorder (P = 0.1658);.;.;Gain of disorder (P = 0.1658);Gain of disorder (P = 0.1658);
MVP
0.38
MPC
0.45
ClinPred
0.19
T
GERP RS
2.9

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.

Other links and lift over

dbSNP: rs777009984; hg19: chr2-179640171; API