rs55933739

Variant summary

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

The NM_001267550.2(TTN):​c.82385C>T​(p.Thr27462Met) variant causes a missense change. The variant allele was found at a frequency of 0.0000886 in 1,613,642 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T27462K) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000090 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:3

Conservation

PhyloP100: 5.27

Publications

7 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=0.05043006).
BP6
Variant 2-178563747-G-A is Benign according to our data. Variant chr2-178563747-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 202911.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.82385C>T p.Thr27462Met missense_variant Exon 326 of 363 ENST00000589042.5 NP_001254479.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.82385C>T p.Thr27462Met missense_variant Exon 326 of 363 5 NM_001267550.2 ENSP00000467141.1

Frequencies

GnomAD3 genomes
AF:
0.0000724
AC:
11
AN:
152022
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000483
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000621
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000604
AC:
15
AN:
248482
AF XY:
0.0000964
show subpopulations
Gnomad AFR exome
AF:
0.0000646
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:
0.0000534
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000903
AC:
132
AN:
1461502
Hom.:
0
Cov.:
37
AF XY:
0.000106
AC XY:
77
AN XY:
727044
show subpopulations
African (AFR)
AF:
0.0000896
AC:
3
AN:
33470
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.0000383
AC:
1
AN:
26122
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39664
South Asian (SAS)
AF:
0.000301
AC:
26
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53394
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5764
European-Non Finnish (NFE)
AF:
0.0000872
AC:
97
AN:
1111754
Other (OTH)
AF:
0.0000663
AC:
4
AN:
60364
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.483
Heterozygous variant carriers
0
9
17
26
34
43
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.0000723
AC:
11
AN:
152140
Hom.:
0
Cov.:
33
AF XY:
0.0000941
AC XY:
7
AN XY:
74380
show subpopulations
African (AFR)
AF:
0.0000482
AC:
2
AN:
41512
American (AMR)
AF:
0.00
AC:
0
AN:
15264
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5156
South Asian (SAS)
AF:
0.000622
AC:
3
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
67994
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.516
Heterozygous variant carriers
0
1
3
4
6
7
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:
0.00
Hom.:
25
Bravo
AF:
0.0000680
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.0000662
AC:
8

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3Benign:1
Sep 15, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 13, 2024
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

BP4_strong -

Feb 25, 2020
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 10, 2019
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 31983221) -

Cardiomyopathy Benign:1
Jul 20, 2021
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Benign:1
Oct 19, 2021
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
0.054
BayesDel_addAF
Benign
-0.37
T
BayesDel_noAF
Benign
-0.47
CADD
Benign
14
DANN
Benign
0.76
Eigen
Benign
-0.80
Eigen_PC
Benign
-0.76
FATHMM_MKL
Benign
0.10
N
LIST_S2
Benign
0.79
T;T;T;.;T;T;T
M_CAP
Uncertain
0.093
D
MetaRNN
Benign
0.050
T;T;T;T;T;T;T
MetaSVM
Benign
-0.77
T
MutationAssessor
Benign
1.6
.;.;.;L;.;.;L
PhyloP100
5.3
PrimateAI
Benign
0.26
T
PROVEAN
Benign
0.030
N;N;.;.;N;N;.
REVEL
Benign
0.18
Sift
Benign
0.038
D;T;.;.;D;D;.
Polyphen
0.082
.;.;.;B;.;.;B
Vest4
0.20
MutPred
0.30
.;.;.;Gain of catalytic residue at T25821 (P = 0.0026);.;.;Gain of catalytic residue at T25821 (P = 0.0026);
MVP
0.20
MPC
0.088
ClinPred
0.036
T
GERP RS
0.93
Mutation Taster
=91/9
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: rs55933739; hg19: chr2-179428474; COSMIC: COSV107420114; COSMIC: COSV107420114; API