rs727503691

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2BP4

The NM_001267550.2(TTN):​c.6844T>C​(p.Tyr2282His) variant causes a missense change. The variant allele was found at a frequency of 0.00000248 in 1,613,514 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y2282S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

2
3
12

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.42

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: Uncertain_significance. The variant received 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.27587044).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.6844T>C p.Tyr2282His missense_variant Exon 30 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7
TTNNM_133379.5 linkc.6844T>C p.Tyr2282His missense_variant Exon 30 of 46 ENST00000360870.10 NP_596870.2 Q8WZ42-6Q7Z3B7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.6844T>C p.Tyr2282His missense_variant Exon 30 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7
TTNENST00000360870.10 linkc.6844T>C p.Tyr2282His missense_variant Exon 30 of 46 5 NM_133379.5 ENSP00000354117.4 Q8WZ42-6

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152224
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000482
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1461290
Hom.:
0
Cov.:
33
AF XY:
0.00000138
AC XY:
1
AN XY:
726986
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33466
American (AMR)
AF:
0.00
AC:
0
AN:
44702
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39668
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86246
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53210
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
9.00e-7
AC:
1
AN:
1111722
Other (OTH)
AF:
0.00
AC:
0
AN:
60382
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
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

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:
152224
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74358
show subpopulations
African (AFR)
AF:
0.0000482
AC:
2
AN:
41464
American (AMR)
AF:
0.00
AC:
0
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68040
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.650
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:
0.00
Hom.:
0
Bravo
AF:
0.0000151

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Aug 22, 2013
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 Tyr2282His vari ant in TTN has not been reported in individuals with cardiomyopathy or in large population studies. Tyrosine (Tyr) at position 2282 is not conserved among mamma ls or evolutionarily distant species, which suggests that a change at this posit ion may be tolerated. Additional computational analyses (biochemical amino acid properties, AlignGVGD, PolyPhen2, and SIFT) do not provide strong support for or against an impact to the protein. While the lack of conservation across many sp ecies suggests that this variant is more likely benign, additional information i s needed to fully assess its clinical significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.21
BayesDel_addAF
Benign
-0.18
T
BayesDel_noAF
Benign
-0.50
CADD
Benign
20
DANN
Benign
0.95
Eigen
Benign
0.18
Eigen_PC
Uncertain
0.32
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.95
D;D;D;.;D;D;D;D
M_CAP
Benign
0.018
T
MetaRNN
Benign
0.28
T;T;T;T;T;T;T;T
MetaSVM
Benign
-1.0
T
PhyloP100
5.4
PrimateAI
Benign
0.46
T
PROVEAN
Uncertain
-3.1
D;D;.;.;D;D;.;D
REVEL
Benign
0.15
Sift
Benign
0.44
T;T;.;.;T;T;.;T
Sift4G
Pathogenic
0.0
.;.;.;.;.;.;.;D
Polyphen
0.48, 0.89
.;.;.;P;.;.;P;P
Vest4
0.42
MVP
0.21
MPC
0.20
ClinPred
0.38
T
GERP RS
4.5
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: rs727503691; hg19: chr2-179639147; API