rs764950995

Variant summary

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

The NM_001267550.2(TTN):​c.54999A>T​(p.Glu18333Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000614 in 1,612,632 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000063 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

4
13

Clinical Significance

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

Conservation

PhyloP100: 0.634
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.

PP2
Missense variant in gene, where missense usually causes diseases (based on misZ statistic), TTN. . Gene score misZ -1.1021 (greater than the threshold 3.09). Trascript score misZ 6.9794 (greater than threshold 3.09). GenCC has associacion of gene with dilated cardiomyopathy, tibial muscular dystrophy, early-onset myopathy with fatal cardiomyopathy, autosomal recessive centronuclear myopathy, hypertrophic cardiomyopathy, hypertrophic cardiomyopathy 9, TTN-related myopathy, dilated cardiomyopathy 1G, arrhythmogenic right ventricular cardiomyopathy, myopathy, myofibrillar, 9, with early respiratory failure, familial isolated dilated cardiomyopathy, childhood-onset progressive contractures-limb-girdle weakness-muscle dystrophy syndrome, autosomal recessive limb-girdle muscular dystrophy type 2J.
BP4
Computational evidence support a benign effect (MetaRNN=0.20494902).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTNNM_001267550.2 linkuse as main transcriptc.54999A>T p.Glu18333Asp missense_variant 283/363 ENST00000589042.5 NP_001254479.2
TTN-AS1NR_038272.1 linkuse as main transcriptn.3917+1736T>A intron_variant, non_coding_transcript_variant

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkuse as main transcriptc.54999A>T p.Glu18333Asp missense_variant 283/3635 NM_001267550.2 ENSP00000467141 P1
TTN-AS1ENST00000659121.1 linkuse as main transcriptn.502+4722T>A intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes
AF:
0.0000461
AC:
7
AN:
151920
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
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:
0.0000883
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000403
AC:
1
AN:
248280
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
134704
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:
0.00000890
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000630
AC:
92
AN:
1460712
Hom.:
0
Cov.:
32
AF XY:
0.0000784
AC XY:
57
AN XY:
726640
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:
0.0000828
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000461
AC:
7
AN:
151920
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74192
show subpopulations
Gnomad4 AFR
AF:
0.0000242
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:
0.0000883
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000416
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.00000828
AC:
1
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpJul 24, 2022- -
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpNov 08, 2017- -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)May 23, 2017- -
Cardiovascular phenotype Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsSep 05, 2019The p.E9268D variant (also known as c.27804A>T), located in coding exon 110 of the TTN gene, results from an A to T substitution at nucleotide position 27804. The glutamic acid at codon 9268 is replaced by aspartic acid, an amino acid with highly similar properties. This amino acid position is well 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
0.15
BayesDel_addAF
Benign
-0.098
T
BayesDel_noAF
Benign
-0.38
CADD
Benign
13
DANN
Benign
0.80
Eigen
Uncertain
0.22
Eigen_PC
Benign
0.18
FATHMM_MKL
Uncertain
0.88
D
LIST_S2
Uncertain
0.86
D;D;D;.;D;D;D
M_CAP
Benign
0.025
D
MetaRNN
Benign
0.20
T;T;T;T;T;T;T
MetaSVM
Benign
-0.40
T
MutationAssessor
Benign
1.8
.;.;.;L;.;.;L
MutationTaster
Benign
0.64
D;D;D;D;D;D
PrimateAI
Uncertain
0.62
T
PROVEAN
Benign
-2.1
N;N;.;.;N;N;.
REVEL
Benign
0.20
Sift
Benign
0.082
T;T;.;.;T;T;.
Polyphen
0.96
.;.;.;D;.;.;D
Vest4
0.27
MutPred
0.40
.;.;.;Loss of MoRF binding (P = 0.1786);.;.;Loss of MoRF binding (P = 0.1786);
MVP
0.27
MPC
0.33
ClinPred
0.27
T
GERP RS
3.2

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: rs764950995; hg19: chr2-179467130; API