rs374727686

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 0P and 1B. BP4

The NM_001267550.2(TTN):​c.63463C>T​(p.Arg21155Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000354 in 1,608,510 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000034 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

3
5
9

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 4.77
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 -1 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.3964259).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.63463C>T p.Arg21155Cys missense_variant Exon 305 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.63463C>T p.Arg21155Cys missense_variant Exon 305 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000461
AC:
7
AN:
151940
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000656
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000414
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000589
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000250
AC:
6
AN:
240280
Hom.:
0
AF XY:
0.0000307
AC XY:
4
AN XY:
130446
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000594
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000582
Gnomad SAS exome
AF:
0.0000669
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000926
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000343
AC:
50
AN:
1456570
Hom.:
0
Cov.:
33
AF XY:
0.0000331
AC XY:
24
AN XY:
724200
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000680
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.000117
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000307
Gnomad4 OTH exome
AF:
0.0000499
GnomAD4 genome
AF:
0.0000461
AC:
7
AN:
151940
Hom.:
0
Cov.:
32
AF XY:
0.0000539
AC XY:
4
AN XY:
74182
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000656
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000414
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000589
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000566
Hom.:
0
Bravo
AF:
0.0000491
ESP6500AA
AF:
0.000265
AC:
1
ESP6500EA
AF:
0.00
AC:
0

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1Benign:1
Jun 05, 2015
Eurofins Ntd Llc (ga)
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 15, 2018
GeneDx
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

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. -

not specified Uncertain:1
Nov 28, 2014
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.Arg18587Cys variant in TTN has not been previously reported in individuals with cardiomyopathy, but has been identified in 1/3770 of African American chro mosomes by the NHLBI Exome Sequencing Project (http://evs.gs.washington.edu/EVS/ ; dbSNP rs374727686). Computational prediction tools and conservation analysis s uggest that this variant may impact the protein, though this information is not predictive enough to determine pathogenicity. In summary, the clinical significa nce of the p.Arg18587Cys variant is uncertain. -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
May 03, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Cardiovascular phenotype Uncertain:1
Jan 17, 2020
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.R12090C variant (also known as c.36268C>T), located in coding exon 132 of the TTN gene, results from a C to T substitution at nucleotide position 36268. The arginine at codon 12090 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.17
BayesDel_addAF
Benign
-0.13
T
BayesDel_noAF
Benign
-0.25
CADD
Uncertain
24
DANN
Benign
0.88
Eigen
Pathogenic
0.84
Eigen_PC
Pathogenic
0.83
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.95
D;D;D;.;D;D;D
M_CAP
Benign
0.0088
T
MetaRNN
Benign
0.40
T;T;T;T;T;T;T
MetaSVM
Benign
-0.33
T
MutationAssessor
Benign
1.8
.;.;.;L;.;.;L
PrimateAI
Uncertain
0.67
T
PROVEAN
Pathogenic
-5.7
D;D;.;.;D;D;.
REVEL
Uncertain
0.39
Sift
Uncertain
0.0080
D;D;.;.;D;D;.
Polyphen
1.0
.;.;.;D;.;.;D
Vest4
0.54
MVP
0.68
MPC
0.54
ClinPred
0.52
D
GERP RS
6.0

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs374727686; hg19: chr2-179452671; COSMIC: COSV60286072; COSMIC: COSV60286072; API