rs200550947

Variant summary

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

The NM_001267550.2(TTN):​c.55374C>G​(p.Ser18458Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00064 in 1,610,360 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 13/20 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: š‘“ 0.00060 ( 0 hom., cov: 32)
Exomes š‘“: 0.00064 ( 1 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
4
12

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:6

Conservation

PhyloP100: 1.57

Publications

3 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=0.06986305).
BP6
Variant 2-178601716-G-C is Benign according to our data. Variant chr2-178601716-G-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 165969.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.55374C>G p.Ser18458Arg missense_variant Exon 286 of 363 ENST00000589042.5 NP_001254479.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.55374C>G p.Ser18458Arg missense_variant Exon 286 of 363 5 NM_001267550.2 ENSP00000467141.1

Frequencies

GnomAD3 genomes
AF:
0.000605
AC:
92
AN:
152042
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000193
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:
0.000471
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00116
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000391
AC:
96
AN:
245648
AF XY:
0.000345
show subpopulations
Gnomad AFR exome
AF:
0.000130
Gnomad AMR exome
AF:
0.0000588
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.000702
Gnomad NFE exome
AF:
0.000664
Gnomad OTH exome
AF:
0.000336
GnomAD4 exome
AF:
0.000644
AC:
939
AN:
1458200
Hom.:
1
Cov.:
32
AF XY:
0.000625
AC XY:
453
AN XY:
725164
show subpopulations
African (AFR)
AF:
0.0000902
AC:
3
AN:
33244
American (AMR)
AF:
0.0000452
AC:
2
AN:
44240
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25996
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39556
South Asian (SAS)
AF:
0.0000117
AC:
1
AN:
85236
European-Finnish (FIN)
AF:
0.000808
AC:
43
AN:
53210
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5746
European-Non Finnish (NFE)
AF:
0.000768
AC:
853
AN:
1110774
Other (OTH)
AF:
0.000615
AC:
37
AN:
60198
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.487
Heterozygous variant carriers
0
56
111
167
222
278
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
32
64
96
128
160
<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:
0.000605
AC:
92
AN:
152160
Hom.:
0
Cov.:
32
AF XY:
0.000511
AC XY:
38
AN XY:
74380
show subpopulations
African (AFR)
AF:
0.000192
AC:
8
AN:
41576
American (AMR)
AF:
0.00
AC:
0
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5126
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.000471
AC:
5
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00116
AC:
79
AN:
67964
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.509
Heterozygous variant carriers
0
4
9
13
18
22
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:
0.000759
Hom.:
0
Bravo
AF:
0.000525
TwinsUK
AF:
0.000539
AC:
2
ALSPAC
AF:
0.000519
AC:
2
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.00122
AC:
10
ExAC
AF:
0.000331
AC:
40
EpiCase
AF:
0.00126
EpiControl
AF:
0.000713

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:6Benign:6
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:4Benign:2
Jul 31, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 05, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 23861362) -

Feb 22, 2023
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jun 24, 2013
Biesecker Lab/Clinical Genomics Section, National Institutes of Health
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:research

- -

Nov 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 17, 2022
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1Benign:2
Aug 30, 2021
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: TTN c.47670C>G (p.Ser15890Arg) results in a non-conservative amino acid change located in the A-band domain of the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.00041 in 277010 control chromosomes, predominantly at a frequency of 0.0007 within the Non-Finnish European subpopulation in the gnomAD database. The observed variant frequency within Non-Finnish European control individuals in the gnomAD database is approximately 2 fold of the estimated maximal expected allele frequency for a pathogenic variant in TTN causing Dilated Cardiomyopathy phenotype (0.00039), strongly suggesting that the variant is a benign polymorphism found primarily in populations of Non-Finnish European origin. c.47670C>G has been reported in the literature in one individual affected with Dilated Cardiomyopathy (Roggenbuck_2019). The report does not provide unequivocal conclusions about association of the variant with Dilated Cardiomyopathy. Additionally, one co-occurrence with another pathogenic variant has been reported (exons 346-362 deletion; Roggenbuck_2019), providing supporting evidence for a benign role. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Four ClinVar submitters (evaluation after 2014) cite the variant as uncertain significance (n=3) and likely benign (n=1). Based on the evidence outlined above, the variant was classified as likely benign. -

Aug 27, 2014
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant classified as Uncertain Significance - Favor Benign. The Ser15890Arg var iant in TTN has not been previously reported in individuals with cardiomyopathy, but has been identified in 0.1% (10/8194) of European American chromosomes by t he NHLBI Exome Sequencing Project (http://evs.gs.washington.edu/EVS/; dbSNP rs20 0550947). Computational prediction tools and conservation analysis do not provid e strong support for or against an impact to the protein. In summary, while the clinical significance of the Ser15890Arg variant is uncertain, its frequency sug gests that it is more likely to be benign. -

Apr 09, 2025
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Dec 29, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiomyopathy Benign:1
Mar 16, 2020
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
Jan 02, 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
Pathogenic
0.64
BayesDel_addAF
Benign
-0.29
T
BayesDel_noAF
Benign
-0.27
CADD
Benign
17
DANN
Benign
0.74
Eigen
Benign
0.052
Eigen_PC
Benign
0.028
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.91
D;D;D;.;D;D;D
M_CAP
Benign
0.028
D
MetaRNN
Benign
0.070
T;T;T;T;T;T;T
MetaSVM
Benign
-0.76
T
MutationAssessor
Benign
1.1
.;.;.;L;.;.;L
PhyloP100
1.6
PrimateAI
Uncertain
0.61
T
PROVEAN
Uncertain
-3.0
D;D;.;.;D;D;.
REVEL
Benign
0.27
Sift
Benign
0.17
T;T;.;.;T;T;.
Polyphen
0.99
.;.;.;D;.;.;D
Vest4
0.51
MutPred
0.47
.;.;.;Gain of MoRF binding (P = 0.0184);.;.;Gain of MoRF binding (P = 0.0184);
MVP
0.21
MPC
0.43
ClinPred
0.13
T
GERP RS
1.1
Mutation Taster
=55/45
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: rs200550947; hg19: chr2-179466443; COSMIC: COSV60290388; COSMIC: COSV60290388; API