2-178727308-C-T

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4_ModerateBP6

The NM_001267550.2(TTN):​c.20057G>A​(p.Arg6686Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000136 in 1,612,456 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. R6686R) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000011 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

4
12

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1

Conservation

PhyloP100: 3.66

Publications

1 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 -3 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.22191143).
BP6
Variant 2-178727308-C-T is Benign according to our data. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282. Variant chr2-178727308-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 203282.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.20057G>A p.Arg6686Gln missense_variant Exon 69 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.20057G>A p.Arg6686Gln missense_variant Exon 69 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000395
AC:
6
AN:
152048
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000965
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000242
AC:
6
AN:
247540
AF XY:
0.0000223
show subpopulations
Gnomad AFR exome
AF:
0.0000648
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000446
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000110
AC:
16
AN:
1460290
Hom.:
0
Cov.:
31
AF XY:
0.0000124
AC XY:
9
AN XY:
726356
show subpopulations
African (AFR)
AF:
0.0000599
AC:
2
AN:
33412
American (AMR)
AF:
0.00
AC:
0
AN:
44596
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26098
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39624
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86020
European-Finnish (FIN)
AF:
0.0000188
AC:
1
AN:
53322
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5752
European-Non Finnish (NFE)
AF:
0.00000990
AC:
11
AN:
1111156
Other (OTH)
AF:
0.0000332
AC:
2
AN:
60310
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
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

Exome 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
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152166
Hom.:
0
Cov.:
33
AF XY:
0.0000403
AC XY:
3
AN XY:
74376
show subpopulations
African (AFR)
AF:
0.0000963
AC:
4
AN:
41552
American (AMR)
AF:
0.00
AC:
0
AN:
15260
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5166
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
67974
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000653
Hom.:
0
Bravo
AF:
0.0000264
ESP6500AA
AF:
0.000270
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000331
AC:
4
EpiCase
AF:
0.0000546
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3Benign:1
-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Jan 15, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Clinical Genetics, Academic Medical Center
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Sep 10, 2020
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
May 26, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.087
BayesDel_addAF
Benign
-0.24
T
BayesDel_noAF
Benign
-0.40
CADD
Uncertain
23
DANN
Uncertain
0.98
Eigen
Uncertain
0.25
Eigen_PC
Uncertain
0.42
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Benign
0.75
T;T;.;T
M_CAP
Benign
0.044
D
MetaRNN
Benign
0.22
T;T;T;T
MetaSVM
Benign
-1.0
T
PhyloP100
3.7
PrimateAI
Benign
0.36
T
PROVEAN
Benign
-1.8
N;.;.;.
REVEL
Benign
0.24
Sift
Benign
0.29
T;.;.;.
Polyphen
0.62
.;.;P;P
Vest4
0.31
MVP
0.13
MPC
0.11
ClinPred
0.095
T
GERP RS
6.2
Mutation Taster
=40/60
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs202022304; hg19: chr2-179592035; API