2-178632317-C-T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_001267550.2(TTN):​c.43577G>A​(p.Arg14526Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000281 in 1,607,726 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 17/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00017 ( 1 hom., cov: 32)
Exomes 𝑓: 0.00029 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:9B:7

Conservation

PhyloP100: -0.0940

Publications

5 publications found
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 was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.017071664).
BP6
Variant 2-178632317-C-T is Benign according to our data. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969. Variant chr2-178632317-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 46969.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.43577G>A p.Arg14526Gln missense_variant Exon 236 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.43577G>A p.Arg14526Gln missense_variant Exon 236 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000171
AC:
26
AN:
151934
Hom.:
1
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000169
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:
0.000279
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000965
AC:
23
AN:
238322
AF XY:
0.0000931
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000900
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000167
Gnomad OTH exome
AF:
0.000171
GnomAD4 exome
AF:
0.000293
AC:
426
AN:
1455792
Hom.:
0
Cov.:
32
AF XY:
0.000283
AC XY:
205
AN XY:
723608
show subpopulations
African (AFR)
AF:
0.0000898
AC:
3
AN:
33394
American (AMR)
AF:
0.000114
AC:
5
AN:
43954
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25928
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39296
South Asian (SAS)
AF:
0.0000235
AC:
2
AN:
85232
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53090
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5750
European-Non Finnish (NFE)
AF:
0.000351
AC:
389
AN:
1108994
Other (OTH)
AF:
0.000449
AC:
27
AN:
60154
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
26
52
77
103
129
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
20
40
60
80
100
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000171
AC:
26
AN:
151934
Hom.:
1
Cov.:
32
AF XY:
0.000121
AC XY:
9
AN XY:
74162
show subpopulations
African (AFR)
AF:
0.000169
AC:
7
AN:
41366
American (AMR)
AF:
0.00
AC:
0
AN:
15242
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5156
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10584
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000279
AC:
19
AN:
67982
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000164
Hom.:
0
Bravo
AF:
0.000189
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000362
AC:
3
ExAC
AF:
0.0000497
AC:
6

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:9Benign:7
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3Benign:4
-
Clinical Genetics, Academic Medical Center
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Jun 14, 2019
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 21, 2020
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 31, 2023
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Apr 11, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

TTN: BP4, BS2 -

not specified Uncertain:2
Sep 30, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: TTN c.35873G>A (p.Arg11958Gln) results in a conservative amino acid change located in the I-band region of the encoded protein sequence. Five of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 9.7e-05 in 238322 control chromosomes, predominantly at a frequency of 0.00017 within the Non-Finnish European subpopulation in the gnomAD database. This frequency is not significantly higher than estimated for a pathogenic variant in TTN causing Dilated Cardiomyopathy (9.7e-05 vs 0.00039), allowing no conclusion about variant significance. To our knowledge, no occurrence of c.35873G>A in individuals affected with Dilated Cardiomyopathy and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 46969). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Jan 02, 2013
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The Arg11958Gln variant in TTN has not been reported in the literature nor previ ously identified by our laboratory. This variant has been identified in 3/8288 E uropean American chromosomes from a broad population by the NHLBI Exome Sequenci ng Project (http://evs.gs.washington.edu/EVS/). Arginine (Arg) at position 11958 is poorly conserved in evolution, and 1 species (zebrafish) carries the variant amino acid (Gln) at this position, suggesting this change may be tolerated. Com putational analyses (biochemical amino acid properties, AlignGVGD, PolyPhen2, an d SIFT) suggest that the Arg11958Gln variant may not impact the protein, though this information is not predictive enough to rule out pathogenicity. Additional information is needed to fully assess the clinical significance of the Arg11958G ln variant. -

Autosomal recessive limb-girdle muscular dystrophy type 2J Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Apr 29, 2016
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dilated cardiomyopathy 1G Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Early-onset myopathy with fatal cardiomyopathy Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Myopathy, myofibrillar, 9, with early respiratory failure Benign:1
Jun 01, 2017
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Tibial muscular dystrophy Benign:1
Jun 01, 2017
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Cardiovascular phenotype Benign:1
Mar 23, 2020
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.090
BayesDel_addAF
Benign
-0.38
T
BayesDel_noAF
Benign
-0.51
CADD
Benign
8.5
DANN
Benign
0.92
Eigen
Benign
-1.2
Eigen_PC
Benign
-1.1
FATHMM_MKL
Benign
0.067
N
LIST_S2
Uncertain
0.89
D;D;D;.;D;D;D
M_CAP
Benign
0.0048
T
MetaRNN
Benign
0.017
T;T;T;T;T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
-1.0
.;.;.;N;.;.;N
PhyloP100
-0.094
PrimateAI
Benign
0.26
T
PROVEAN
Benign
0.11
N;N;.;.;N;N;.
REVEL
Benign
0.16
Sift
Benign
0.61
T;T;.;.;T;T;.
Polyphen
0.0030
.;.;.;B;.;.;B
Vest4
0.15
MVP
0.048
MPC
0.097
ClinPred
0.023
T
GERP RS
-5.5
Mutation Taster
=94/6
polymorphism

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

Other links and lift over

dbSNP: rs373491468; hg19: chr2-179497044; COSMIC: COSV100629531; COSMIC: COSV100629531; API