rs201302681

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 1P and 5B. PP2BP4_StrongBP6

The NM_001267550.2(TTN):ā€‹c.50642G>Cā€‹(p.Gly16881Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000329 in 1,613,032 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: š‘“ 0.000020 ( 0 hom., cov: 32)
Exomes š‘“: 0.000034 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

4
6
7

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:2

Conservation

PhyloP100: 7.86
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 -4 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=0.032815933).
BP6
Variant 2-178611587-C-G is Benign according to our data. Variant chr2-178611587-C-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 229448.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=2}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTNNM_001267550.2 linkuse as main transcriptc.50642G>C p.Gly16881Ala missense_variant 269/363 ENST00000589042.5 NP_001254479.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkuse as main transcriptc.50642G>C p.Gly16881Ala missense_variant 269/3635 NM_001267550.2 ENSP00000467141 P1
TTN-AS1ENST00000659121.1 linkuse as main transcriptn.502+13906C>G intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152018
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000584
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000190
AC:
47
AN:
247948
Hom.:
0
AF XY:
0.000171
AC XY:
23
AN XY:
134494
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00264
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000342
AC:
50
AN:
1460896
Hom.:
0
Cov.:
33
AF XY:
0.0000358
AC XY:
26
AN XY:
726760
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00124
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152136
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74364
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000585
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000642
ExAC
AF:
0.000166
AC:
20

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineMar 18, 2015Variant classified as Uncertain Significance - Favor Benign. The p.Gly14313Ala v ariant in TTN has not been previously reported in individuals with cardiomyopath y, but has been identified in 0.2% (20/8446) of East Asian chromosomes by the Ex ome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs201302 681). Computational prediction tools and conservation analysis suggest that the p.Gly14313Ala variant may impact the protein, though this information is not pre dictive enough to determine pathogenicity. In summary, while the clinical signif icance of the p.Gly14313Ala variant is uncertain, its frequency suggests that it is more likely to be benign. -
Cardiovascular phenotype Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsMay 09, 2013There is insufficient or conflicting evidence for classification of this alteration. -
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Benign:1
Likely benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 21, 2024- -
not provided Benign:1
Likely benign, criteria provided, single submitterclinical testingGeneDxDec 10, 2020- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.81
BayesDel_addAF
Benign
-0.27
T
BayesDel_noAF
Benign
-0.17
CADD
Benign
22
DANN
Benign
0.97
Eigen
Pathogenic
0.90
Eigen_PC
Pathogenic
0.90
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.94
D;D;D;.;D;D;D
M_CAP
Benign
0.012
T
MetaRNN
Benign
0.033
T;T;T;T;T;T;T
MetaSVM
Uncertain
-0.10
T
MutationAssessor
Benign
1.8
.;.;.;L;.;.;L
MutationTaster
Benign
1.0
D;D;D;D;D;D
PrimateAI
Uncertain
0.61
T
PROVEAN
Uncertain
-4.3
D;D;.;.;D;D;.
REVEL
Uncertain
0.43
Sift
Uncertain
0.0080
D;D;.;.;D;D;.
Polyphen
1.0
.;.;.;D;.;.;D
Vest4
0.52
MutPred
0.49
.;.;.;Gain of ubiquitination at K15237 (P = 0.1108);.;.;Gain of ubiquitination at K15237 (P = 0.1108);
MVP
0.36
MPC
0.48
ClinPred
0.18
T
GERP RS
6.0

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.050
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: rs201302681; hg19: chr2-179476314; API