rs876658088

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_001267550.2(TTN):​c.84494A>G​(p.His28165Arg) variant causes a missense change. The variant allele was found at a frequency of 0.0000143 in 1,611,178 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
3
13

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 4.91

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: Likely_benign. The variant received -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.22382215).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.84494A>G p.His28165Arg missense_variant Exon 326 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.84494A>G p.His28165Arg missense_variant Exon 326 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152194
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.0000144
AC:
21
AN:
1458984
Hom.:
0
Cov.:
32
AF XY:
0.0000124
AC XY:
9
AN XY:
725622
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33374
American (AMR)
AF:
0.00
AC:
0
AN:
44494
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25972
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39556
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53210
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5746
European-Non Finnish (NFE)
AF:
0.0000189
AC:
21
AN:
1110554
Other (OTH)
AF:
0.00
AC:
0
AN:
60244
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
Heterozygous variant carriers
0
2
4
7
9
11
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:
0.0000131
AC:
2
AN:
152194
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74358
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41456
American (AMR)
AF:
0.00
AC:
0
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.325
Heterozygous variant carriers
0
1
1
2
2
3
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.:
0

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
Oct 15, 2014
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.His25597Arg variant in TTN has not been previously reported in individuals with cardiomyopathy or in large population studies. Computational prediction to ols and conservation analysis do not provide strong support for or against an im pact to the protein. In summary, the clinical significance of the p.His25597Arg variant is uncertain. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.10
BayesDel_addAF
Benign
-0.062
T
BayesDel_noAF
Benign
-0.33
CADD
Benign
18
DANN
Benign
0.89
Eigen
Benign
0.089
Eigen_PC
Uncertain
0.27
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Benign
0.80
T;T;T;.;T;T;T
M_CAP
Benign
0.020
T
MetaRNN
Benign
0.22
T;T;T;T;T;T;T
MetaSVM
Benign
-0.96
T
MutationAssessor
Benign
0.66
.;.;.;N;.;.;N
PhyloP100
4.9
PrimateAI
Uncertain
0.58
T
PROVEAN
Pathogenic
-5.2
D;D;.;.;D;D;.
REVEL
Benign
0.16
Sift
Benign
0.063
T;T;.;.;T;T;.
Polyphen
0.38
.;.;.;B;.;.;B
Vest4
0.46
MVP
0.14
MPC
0.14
ClinPred
0.26
T
GERP RS
4.8
Mutation Taster
=38/62
disease causing

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: rs876658088; hg19: chr2-179426365; API