rs368450420

Variant summary

Our verdict is Benign. The variant received -8 ACMG points: 0P and 8B. BP4_ModerateBP6BP7BS1

The NM_001267550.2(TTN):​c.55659G>A​(p.Val18553Val) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000103 in 1,610,336 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts 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. V18553V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00059 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000052 ( 1 hom. )

Consequence

TTN
NM_001267550.2 synonymous

Scores

2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:8

Conservation

PhyloP100: -0.475

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: Benign. The variant received -8 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.37).
BP6
Variant 2-178601338-C-T is Benign according to our data. Variant chr2-178601338-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 263665.
BP7
Synonymous conserved (PhyloP=-0.475 with no splicing effect.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.000592 (90/152152) while in subpopulation AFR AF = 0.00195 (81/41562). AF 95% confidence interval is 0.00161. There are 0 homozygotes in GnomAd4. There are 34 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.55659G>A p.Val18553Val synonymous_variant Exon 287 of 363 ENST00000589042.5 NP_001254479.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.55659G>A p.Val18553Val synonymous_variant Exon 287 of 363 5 NM_001267550.2 ENSP00000467141.1

Frequencies

GnomAD3 genomes
AF:
0.000592
AC:
90
AN:
152034
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00195
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000525
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:
0.00
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000191
AC:
47
AN:
246546
AF XY:
0.0000898
show subpopulations
Gnomad AFR exome
AF:
0.00253
Gnomad AMR exome
AF:
0.000146
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000335
GnomAD4 exome
AF:
0.0000521
AC:
76
AN:
1458184
Hom.:
1
Cov.:
32
AF XY:
0.0000483
AC XY:
35
AN XY:
724956
show subpopulations
African (AFR)
AF:
0.00165
AC:
55
AN:
33366
American (AMR)
AF:
0.000157
AC:
7
AN:
44540
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26026
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39454
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53316
Middle Eastern (MID)
AF:
0.000174
AC:
1
AN:
5748
European-Non Finnish (NFE)
AF:
9.01e-7
AC:
1
AN:
1109690
Other (OTH)
AF:
0.000199
AC:
12
AN:
60220
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.497
Heterozygous variant carriers
0
4
8
13
17
21
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.000592
AC:
90
AN:
152152
Hom.:
0
Cov.:
32
AF XY:
0.000457
AC XY:
34
AN XY:
74380
show subpopulations
African (AFR)
AF:
0.00195
AC:
81
AN:
41562
American (AMR)
AF:
0.000524
AC:
8
AN:
15254
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5134
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67964
Other (OTH)
AF:
0.000473
AC:
1
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.503
Heterozygous variant carriers
0
4
8
13
17
21
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:
0.000442
Hom.:
1
Bravo
AF:
0.000756

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:8
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Benign:4
Jun 11, 2015
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Apr 15, 2021
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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

- -

May 20, 2024
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1Benign:1
-
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

- -

Jan 04, 2018
Eurofins Ntd Llc (ga)
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 Benign:1
Jan 29, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiomyopathy Benign:1
Jun 21, 2023
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Benign:1
Jun 11, 2013
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: 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
BayesDel_noAF
Benign
-0.37
CADD
Benign
0.37
DANN
Benign
0.82
PhyloP100
-0.47
Mutation Taster
=88/12
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: rs368450420; hg19: chr2-179466065; API