chr2-178559697-A-G

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 0P and 0B.

The NM_001267550.2(TTN):​c.86435T>C​(p.Ile28812Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000018 in 1,607,668 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I28812V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

3
11
3

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 9.27

Publications

0 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: Uncertain_significance. The variant received 0 ACMG points.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.86435T>C p.Ile28812Thr missense_variant Exon 326 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.86435T>C p.Ile28812Thr missense_variant Exon 326 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152124
Hom.:
0
Cov.:
33
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:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000165
AC:
4
AN:
242466
AF XY:
0.0000305
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000293
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000480
Gnomad NFE exome
AF:
0.0000182
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000179
AC:
26
AN:
1455426
Hom.:
0
Cov.:
32
AF XY:
0.0000180
AC XY:
13
AN XY:
723474
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33336
American (AMR)
AF:
0.0000226
AC:
1
AN:
44304
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25596
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39650
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85024
European-Finnish (FIN)
AF:
0.0000943
AC:
5
AN:
52996
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5734
European-Non Finnish (NFE)
AF:
0.0000153
AC:
17
AN:
1108682
Other (OTH)
AF:
0.0000499
AC:
3
AN:
60104
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
2
4
5
7
9
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:
0.0000197
AC:
3
AN:
152242
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74438
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41546
American (AMR)
AF:
0.00
AC:
0
AN:
15296
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5160
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68016
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000571
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.0000248
AC:
3

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Feb 06, 2014
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The Ile26244Thr variant in TTN has not been previously reported in individuals w ith cardiomyopathy or in large population studies. Computational analyses (bioch emical amino acid properties, conservation, AlignGVGD, PolyPhen2, and SIFT) do n ot provide strong support for or against an impact to the protein. Additional in formation is needed to fully assess the clinical significance of the variant. -

Cardiomyopathy Uncertain:1
Oct 13, 2021
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
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
Uncertain
0.44
BayesDel_addAF
Uncertain
0.10
D
BayesDel_noAF
Uncertain
-0.010
CADD
Benign
21
DANN
Benign
0.85
Eigen
Uncertain
0.47
Eigen_PC
Uncertain
0.56
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.94
D;D;D;.;D;D;D
M_CAP
Benign
0.077
D
MetaRNN
Uncertain
0.51
D;D;D;D;D;D;D
MetaSVM
Uncertain
0.27
D
MutationAssessor
Pathogenic
4.2
.;.;.;H;.;.;H
PhyloP100
9.3
PrimateAI
Uncertain
0.54
T
PROVEAN
Uncertain
-3.8
D;D;.;.;D;D;.
REVEL
Pathogenic
0.76
Sift
Uncertain
0.0010
D;D;.;.;D;D;.
Polyphen
0.12
.;.;.;B;.;.;B
Vest4
0.31
MutPred
0.81
.;.;.;Gain of glycosylation at I27171 (P = 0.0103);.;.;Gain of glycosylation at I27171 (P = 0.0103);
MVP
0.76
MPC
0.14
ClinPred
0.44
T
GERP RS
5.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Mutation Taster
=78/22
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: rs727504959; hg19: chr2-179424424; API