chr2-178714493-C-T

Variant summary

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

The NM_001267550.2(TTN):​c.26281G>A​(p.Gly8761Ser) variant causes a missense change. The variant allele was found at a frequency of 0.000142 in 1,613,350 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 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00015 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

5
3
8

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:1

Conservation

PhyloP100: 6.13
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 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=0.4212928).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTNNM_001267550.2 linkuse as main transcriptc.26281G>A p.Gly8761Ser missense_variant 91/363 ENST00000589042.5 NP_001254479.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkuse as main transcriptc.26281G>A p.Gly8761Ser missense_variant 91/3635 NM_001267550.2 ENSP00000467141 P1
TTN-AS1ENST00000659121.1 linkuse as main transcriptn.503-20011C>T intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152120
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000564
AC:
14
AN:
248070
Hom.:
0
AF XY:
0.0000669
AC XY:
9
AN XY:
134596
show subpopulations
Gnomad AFR exome
AF:
0.0000647
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:
0.000116
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000151
AC:
221
AN:
1461230
Hom.:
0
Cov.:
33
AF XY:
0.000151
AC XY:
110
AN XY:
726882
show subpopulations
Gnomad4 AFR exome
AF:
0.0000897
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:
0.000193
Gnomad4 OTH exome
AF:
0.0000497
GnomAD4 genome
AF:
0.0000526
AC:
8
AN:
152120
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74296
show subpopulations
Gnomad4 AFR
AF:
0.0000724
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:
0.0000735
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000990
Hom.:
0
Bravo
AF:
0.0000529
ESP6500AA
AF:
0.000268
AC:
1
ESP6500EA
AF:
0.000122
AC:
1
ExAC
AF:
0.0000497
AC:
6
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:6Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:4Benign:1
Likely benign, criteria provided, single submitterclinical testingGeneDxMar 02, 2021- -
Uncertain significance, no assertion criteria providedclinical testingClinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center-- -
Uncertain significance, criteria provided, single submitterclinical testingMayo Clinic Laboratories, Mayo ClinicNov 30, 2021- -
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)Aug 10, 2018- -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpDec 26, 2021- -
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 28, 2017- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.58
BayesDel_addAF
Benign
-0.12
T
BayesDel_noAF
Benign
-0.18
CADD
Benign
23
DANN
Benign
0.92
Eigen
Pathogenic
0.94
Eigen_PC
Pathogenic
0.88
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Benign
0.84
T;D;.;T
M_CAP
Benign
0.058
D
MetaRNN
Benign
0.42
T;T;T;T
MetaSVM
Uncertain
0.62
D
MutationTaster
Benign
1.0
D;D;D;D;D;D
PrimateAI
Uncertain
0.51
T
PROVEAN
Uncertain
-3.3
D;.;.;.
REVEL
Pathogenic
0.67
Sift
Benign
0.45
T;.;.;.
Polyphen
1.0
.;.;D;D
Vest4
0.39
MVP
0.56
MPC
0.46
ClinPred
0.18
T
GERP RS
6.0

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs369385294; hg19: chr2-179579220; API