chr2-178575647-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 1P and 1B. PP2BP4

The NM_001267550.2(TTN):​c.70485A>T​(p.Lys23495Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000144 in 1,461,378 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 11/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
6
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:8

Conservation

PhyloP100: 0.648
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 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=0.26935118).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTNNM_001267550.2 linkuse as main transcriptc.70485A>T p.Lys23495Asn missense_variant 326/363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkuse as main transcriptc.70485A>T p.Lys23495Asn missense_variant 326/3635 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD3 exomes
AF:
0.0000201
AC:
5
AN:
248558
Hom.:
0
AF XY:
0.00000742
AC XY:
1
AN XY:
134832
show subpopulations
Gnomad AFR exome
AF:
0.0000646
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:
0.0000356
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000144
AC:
21
AN:
1461378
Hom.:
0
Cov.:
36
AF XY:
0.0000165
AC XY:
12
AN XY:
726970
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
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:
0.0000153
Gnomad4 OTH exome
AF:
0.0000497
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.0000936
Hom.:
0
Bravo
AF:
0.00000756
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:6
Uncertain significance, criteria provided, single submitterclinical testingMayo Clinic Laboratories, Mayo ClinicDec 07, 2023- -
Uncertain significance, criteria provided, single submitternot providedBreakthrough Genomics, Breakthrough Genomics-- -
Uncertain significance, criteria provided, single submitterclinical testingRevvity Omics, RevvityDec 22, 2020- -
Uncertain significance, no assertion criteria providedclinical testingClinical Genetics, Academic Medical Center-- -
Uncertain significance, no assertion criteria providedclinical testingJoint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+-- -
Uncertain significance, no assertion criteria providedclinical testingDiagnostic Laboratory, Department of Genetics, University Medical Center Groningen-- -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAthena DiagnosticsFeb 10, 2017- -
Cardiovascular phenotype Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsFeb 11, 2020The p.K14430N variant (also known as c.43290A>T), located in coding exon 153 of the TTN gene, results from an A to T substitution at nucleotide position 43290. The lysine at codon 14430 is replaced by asparagine, an amino acid with similar properties. This amino acid position is not 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
Pathogenic
0.76
BayesDel_addAF
Benign
-0.28
T
BayesDel_noAF
Benign
-0.46
CADD
Benign
16
DANN
Benign
0.94
Eigen
Uncertain
0.30
Eigen_PC
Uncertain
0.25
FATHMM_MKL
Uncertain
0.90
D
LIST_S2
Benign
0.80
T;T;T;.;T;T;T
M_CAP
Benign
0.033
D
MetaRNN
Benign
0.27
T;T;T;T;T;T;T
MetaSVM
Benign
-0.64
T
MutationAssessor
Uncertain
2.5
.;.;.;M;.;.;M
PrimateAI
Uncertain
0.59
T
PROVEAN
Uncertain
-3.1
D;D;.;.;D;D;.
REVEL
Benign
0.26
Sift
Benign
0.040
D;D;.;.;D;D;.
Polyphen
0.99
.;.;.;D;.;.;D
Vest4
0.34
MutPred
0.56
.;.;.;Loss of ubiquitination at K21854 (P = 0.0167);.;.;Loss of ubiquitination at K21854 (P = 0.0167);
MVP
0.14
MPC
0.39
ClinPred
0.29
T
GERP RS
2.1

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: rs1482776876; hg19: chr2-179440374; API