2-178545991-C-T

Variant summary

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

The NM_001267550.2(TTN):​c.95245G>A​(p.Glu31749Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000607 in 1,613,782 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000053 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

5
4
8

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:9

Conservation

PhyloP100: 7.91
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=0.27091545).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTNNM_001267550.2 linkuse as main transcriptc.95245G>A p.Glu31749Lys missense_variant 343/363 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.95245G>A p.Glu31749Lys missense_variant 343/3635 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000125
AC:
19
AN:
152144
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000266
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:
0.000118
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000805
AC:
20
AN:
248548
Hom.:
0
AF XY:
0.0000668
AC XY:
9
AN XY:
134830
show subpopulations
Gnomad AFR exome
AF:
0.000258
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:
0.000124
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000534
AC:
78
AN:
1461520
Hom.:
0
Cov.:
33
AF XY:
0.0000509
AC XY:
37
AN XY:
727040
show subpopulations
Gnomad4 AFR exome
AF:
0.0000896
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000232
Gnomad4 FIN exome
AF:
0.0000375
Gnomad4 NFE exome
AF:
0.0000630
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.000131
AC:
20
AN:
152262
Hom.:
0
Cov.:
33
AF XY:
0.000134
AC XY:
10
AN XY:
74458
show subpopulations
Gnomad4 AFR
AF:
0.000289
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:
0.000118
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000197
Hom.:
0
Bravo
AF:
0.000102
ESP6500AA
AF:
0.000248
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000116
AC:
14
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:9
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:5
Uncertain significance, criteria provided, single submitterclinical testingGeneDxJul 01, 2024In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 24636144) -
Uncertain significance, criteria provided, single submitterclinical testingRevvity Omics, RevvityApr 18, 2019- -
Uncertain significance, no assertion criteria providedclinical testingClinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center-- -
Uncertain significance, no assertion criteria providedclinical testingJoint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+-- -
Uncertain significance, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Feb 23, 2017- -
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJul 27, 2017- -
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1838244:Tibial muscular dystrophy;C1858763:Dilated cardiomyopathy 1G;C1861065:Hypertrophic cardiomyopathy 9;C1863599:Myopathy, myofibrillar, 9, with early respiratory failure;C2673677:Early-onset myopathy with fatal cardiomyopathy Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsJul 01, 2021- -
Cardiovascular phenotype Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsFeb 18, 2013​The p.E29181K variant (also known as c.87541G>A) is located in coding exon 291 of the TTN gene. This alteration results from a G to A substitution at nucleotide position 87541. The glutamate at codon 29181 is replaced by lysine, an amino acid with similar properties. This variant was observed in conjunction with a pathogenic PKP2 mutation in a proband tested by our laboratory who is affected with ADHD, sudden cardiac arrest and syncope. This variant was previously reported in the SNPDatabase as rs139542862. Based on data from the NHLBI Exome Sequencing Project (ESP), the A-allele has an overall frequency of approximately 0.01% (1/12,398), having been observed in 0.02% (1/4038) of African American alleles and in 0% (0/8360) of European American alleles studied. Based on data from the 1000 Genomes Project, the A-allele has an overall frequency of approximately 0.05% (1/2184). The highest observed frequency was 1 of 194 (0.52%) Luhya West African chromosomes. Based on protein sequence alignment, this amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be probably damaging by PolyPhen in silico analysis. Since supporting evidence is limited at this time, the clinical significance of p.E29181K remains unclear. -
Ventricular tachycardia Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingCenter for Advanced Laboratory Medicine, UC San Diego Health, University of California San DiegoSep 21, 2017- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
BayesDel_addAF
Benign
-0.20
T
BayesDel_noAF
Benign
-0.23
CADD
Benign
23
DANN
Uncertain
0.98
Eigen
Pathogenic
0.86
Eigen_PC
Pathogenic
0.85
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.98
D;D;D;.;D;D;D
M_CAP
Benign
0.031
D
MetaRNN
Benign
0.27
T;T;T;T;T;T;T
MetaSVM
Benign
-0.34
T
MutationAssessor
Benign
1.5
.;.;.;L;.;.;L
PrimateAI
Uncertain
0.78
T
PROVEAN
Uncertain
-2.9
D;D;.;.;D;D;.
REVEL
Uncertain
0.42
Sift
Benign
0.035
D;D;.;.;D;D;.
Polyphen
1.0
.;.;.;D;.;.;D
Vest4
0.62
MVP
0.42
MPC
0.49
ClinPred
0.19
T
GERP RS
5.8

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: rs139542862; hg19: chr2-179410718; COSMIC: COSV104645729; COSMIC: COSV104645729; API