rs763065439

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 0P and 3B. BP4_ModerateBS1_Supporting

The NM_001267550.2(TTN):​c.13376T>C​(p.Ile4459Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000818 in 1,613,804 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 13/18 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000083 ( 1 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
1
14

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 9.19
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 -3 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.20446372).
BS1
Variant frequency is greater than expected in population mid. gnomad4_exome allele frequency = 0.0000828 (121/1461630) while in subpopulation MID AF= 0.00295 (17/5766). AF 95% confidence interval is 0.00188. There are 1 homozygotes in gnomad4_exome. There are 67 alleles in male gnomad4_exome subpopulation. Median coverage is 31. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.13376T>C p.Ile4459Thr missense_variant Exon 48 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.13376T>C p.Ile4459Thr missense_variant Exon 48 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000723
AC:
11
AN:
152174
Hom.:
0
Cov.:
32
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:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000118
Gnomad OTH
AF:
0.000478
GnomAD3 exomes
AF:
0.0000644
AC:
16
AN:
248586
Hom.:
0
AF XY:
0.0000593
AC XY:
8
AN XY:
134814
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
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:
0.000125
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000828
AC:
121
AN:
1461630
Hom.:
1
Cov.:
31
AF XY:
0.0000921
AC XY:
67
AN XY:
727100
show subpopulations
Gnomad4 AFR exome
AF:
0.0000597
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000348
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000818
Gnomad4 OTH exome
AF:
0.000116
GnomAD4 genome
AF:
0.0000723
AC:
11
AN:
152174
Hom.:
0
Cov.:
32
AF XY:
0.0000942
AC XY:
7
AN XY:
74328
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:
0.000207
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.000118
Gnomad4 OTH
AF:
0.000478
Alfa
AF:
0.000115
Hom.:
1
Bravo
AF:
0.0000529
ExAC
AF:
0.0000662
AC:
8
EpiCase
AF:
0.000273
EpiControl
AF:
0.000119

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:4
Sep 29, 2015
Eurofins Ntd Llc (ga)
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Dec 01, 2022
CeGaT Center for Human Genetics Tuebingen
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

TTN: PM2, BP4 -

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

- -

not specified Uncertain:1
Sep 09, 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.Ile4221Thr variant in TTN has not been previously identified in individual s with cardiomyopathy, but has been identified in 8/66718 European chromosomes b y the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org). Compu tational prediction tools and conservation analysis do not provide strong suppor t for or against an impact to the protein. In summary, the clinical significance of the p.Ile4221Thr variant is uncertain. -

See cases Uncertain:1
Sep 23, 2021
Laboratorio de Genetica e Diagnostico Molecular, Hospital Israelita Albert Einstein
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

ACMG classification criteria: BP4 -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.22
BayesDel_addAF
Benign
-0.23
T
BayesDel_noAF
Benign
-0.33
CADD
Benign
19
DANN
Benign
0.80
Eigen
Benign
-0.014
Eigen_PC
Benign
0.092
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Benign
0.77
T;T;.;T;T;T
M_CAP
Benign
0.046
D
MetaRNN
Benign
0.20
T;T;T;T;T;T
MetaSVM
Benign
-0.74
T
PrimateAI
Benign
0.34
T
PROVEAN
Uncertain
-2.5
D;.;.;D;D;.
REVEL
Benign
0.24
Sift
Benign
0.038
D;.;.;D;D;.
Vest4
0.22
MVP
0.73
MPC
0.11
ClinPred
0.17
T
GERP RS
5.6

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: rs763065439; hg19: chr2-179604584; API