rs199710082

Variant summary

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

The NM_001267550.2(TTN):​c.104519G>A​(p.Arg34840Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000057 in 1,613,756 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. R34840W) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00019 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000043 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

3
6
8

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:2

Conservation

PhyloP100: 7.33

Publications

4 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=0.1466066).
BP6
Variant 2-178532096-C-T is Benign according to our data. Variant chr2-178532096-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 203082.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.104519G>A p.Arg34840Gln missense_variant Exon 358 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.104519G>A p.Arg34840Gln missense_variant Exon 358 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000191
AC:
29
AN:
152124
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000580
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.000377
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000925
AC:
23
AN:
248764
AF XY:
0.0000667
show subpopulations
Gnomad AFR exome
AF:
0.000711
Gnomad AMR exome
AF:
0.0000870
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000111
Gnomad FIN exome
AF:
0.000186
Gnomad NFE exome
AF:
0.00000888
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000431
AC:
63
AN:
1461632
Hom.:
0
Cov.:
40
AF XY:
0.0000371
AC XY:
27
AN XY:
727104
show subpopulations
African (AFR)
AF:
0.000657
AC:
22
AN:
33476
American (AMR)
AF:
0.0000671
AC:
3
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39690
South Asian (SAS)
AF:
0.0000696
AC:
6
AN:
86256
European-Finnish (FIN)
AF:
0.000300
AC:
16
AN:
53372
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000809
AC:
9
AN:
1111840
Other (OTH)
AF:
0.0000828
AC:
5
AN:
60374
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.503
Heterozygous variant carriers
0
5
11
16
22
27
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:
0.000191
AC:
29
AN:
152124
Hom.:
0
Cov.:
32
AF XY:
0.000256
AC XY:
19
AN XY:
74308
show subpopulations
African (AFR)
AF:
0.000580
AC:
24
AN:
41412
American (AMR)
AF:
0.0000655
AC:
1
AN:
15274
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.000377
AC:
4
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
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

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:
0.000116
Hom.:
0
Bravo
AF:
0.000185
ESP6500AA
AF:
0.000497
AC:
2
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000107
AC:
13
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:6Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:4Benign:1
Sep 24, 2023
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jun 06, 2017
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Jan 30, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Dec 06, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Uncertain:1
Jan 14, 2019
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R25775Q variant (also known as c.77324G>A), located in coding exon 185 of the TTN gene, results from a G to A substitution at nucleotide position 77324. The arginine at codon 25775 is replaced by glutamine, an amino acid with highly similar properties. This variant was reported (as NM_001267550.1:c.104519G>A p.R34840Q) in an individual with restrictive cardiomyopathy, who also had additional cardiac variants detected (Kostareva A et al. PLoS ONE Sep;11:e0163362). This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Cardiomyopathy Benign:1
Aug 31, 2018
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.24
BayesDel_addAF
Benign
-0.21
T
BayesDel_noAF
Benign
-0.17
CADD
Benign
21
DANN
Benign
0.92
Eigen
Pathogenic
0.68
Eigen_PC
Pathogenic
0.72
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.96
D;D;D;.;D;D;D
M_CAP
Benign
0.046
D
MetaRNN
Benign
0.15
T;T;T;T;T;T;T
MetaSVM
Uncertain
0.18
D
MutationAssessor
Benign
0.0
.;.;.;N;.;.;N
PhyloP100
7.3
PrimateAI
Uncertain
0.62
T
PROVEAN
Uncertain
-2.6
D;D;.;.;D;D;.
REVEL
Uncertain
0.41
Sift
Uncertain
0.014
D;D;.;.;D;D;.
Polyphen
1.0
.;.;.;D;.;.;D
Vest4
0.53
MVP
0.48
MPC
0.49
ClinPred
0.15
T
GERP RS
5.5
Mutation Taster
=90/10
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: rs199710082; hg19: chr2-179396823; COSMIC: COSV60187545; COSMIC: COSV60187545; API