rs143193258

Variant summary

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

The NM_001267550.2(TTN):​c.88514G>A​(p.Arg29505His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000044 in 1,613,788 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts 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. R29505C) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000046 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

3
7
7

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:1

Conservation

PhyloP100: 7.87

Publications

5 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=0.13304222).
BP6
Variant 2-178554945-C-T is Benign according to our data. Variant chr2-178554945-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 404962.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.88514G>A p.Arg29505His missense_variant Exon 331 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.88514G>A p.Arg29505His missense_variant Exon 331 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152158
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000196
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000966
AC:
24
AN:
248462
AF XY:
0.0000816
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000609
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000267
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000458
AC:
67
AN:
1461512
Hom.:
0
Cov.:
32
AF XY:
0.0000426
AC XY:
31
AN XY:
727038
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33478
American (AMR)
AF:
0.000492
AC:
22
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39622
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53378
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000360
AC:
40
AN:
1111800
Other (OTH)
AF:
0.00
AC:
0
AN:
60362
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.486
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:
0.0000263
AC:
4
AN:
152276
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74438
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41576
American (AMR)
AF:
0.000196
AC:
3
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10600
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68014
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000434
Hom.:
0
Bravo
AF:
0.0000416
ExAC
AF:
0.0000497
AC:
6

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Jul 28, 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
Sep 09, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Jun 10, 2019
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Benign:1
Dec 17, 2019
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
Uncertain
0.49
BayesDel_addAF
Benign
-0.29
T
BayesDel_noAF
Benign
-0.30
CADD
Benign
23
DANN
Benign
0.96
Eigen
Pathogenic
0.75
Eigen_PC
Pathogenic
0.71
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.94
D;D;D;.;D;D;D
M_CAP
Benign
0.022
T
MetaRNN
Benign
0.13
T;T;T;T;T;T;T
MetaSVM
Benign
-0.62
T
MutationAssessor
Uncertain
2.7
.;.;.;M;.;.;M
PhyloP100
7.9
PrimateAI
Uncertain
0.57
T
PROVEAN
Uncertain
-3.6
D;D;.;.;D;D;.
REVEL
Uncertain
0.37
Sift
Uncertain
0.0030
D;D;.;.;D;D;.
Polyphen
1.0
.;.;.;D;.;.;D
Vest4
0.41
MVP
0.18
MPC
0.52
ClinPred
0.32
T
GERP RS
5.7
Mutation Taster
=72/28
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: rs143193258; hg19: chr2-179419672; COSMIC: COSV60098127; COSMIC: COSV60098127; API