rs372881122

Variant summary

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

The NM_001267550.2(TTN):​c.47866G>A​(p.Asp15956Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000155 in 1,609,932 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000011 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

3
7
7

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 7.85

Publications

2 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=0.17852408).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.47866G>A p.Asp15956Asn missense_variant Exon 255 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.47866G>A p.Asp15956Asn missense_variant Exon 255 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000593
AC:
9
AN:
151872
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000169
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000195
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000246
AC:
6
AN:
244110
AF XY:
0.0000151
show subpopulations
Gnomad AFR exome
AF:
0.000263
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000908
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000110
AC:
16
AN:
1457942
Hom.:
0
Cov.:
32
AF XY:
0.00000827
AC XY:
6
AN XY:
725078
show subpopulations
African (AFR)
AF:
0.000180
AC:
6
AN:
33318
American (AMR)
AF:
0.00
AC:
0
AN:
44310
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26042
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39306
South Asian (SAS)
AF:
0.0000117
AC:
1
AN:
85662
European-Finnish (FIN)
AF:
0.0000188
AC:
1
AN:
53254
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5748
European-Non Finnish (NFE)
AF:
0.00000631
AC:
7
AN:
1110124
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60178
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.469
Heterozygous variant carriers
0
1
3
4
6
7
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:
0.0000592
AC:
9
AN:
151990
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74308
show subpopulations
African (AFR)
AF:
0.000169
AC:
7
AN:
41514
American (AMR)
AF:
0.00
AC:
0
AN:
15250
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000195
AC:
1
AN:
5118
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67876
Other (OTH)
AF:
0.00
AC:
0
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000985
Hom.:
0
Bravo
AF:
0.0000680
ESP6500AA
AF:
0.000269
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000415
AC:
5

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

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

- -

Cardiovascular phenotype Uncertain:1
Jul 29, 2019
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.D6891N variant (also known as c.20671G>A), located in coding exon 82 of the TTN gene, results from a G to A substitution at nucleotide position 20671. The aspartic acid at codon 6891 is replaced by asparagine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.18
BayesDel_addAF
Benign
-0.31
T
BayesDel_noAF
Benign
-0.37
CADD
Benign
23
DANN
Benign
0.95
Eigen
Pathogenic
0.89
Eigen_PC
Pathogenic
0.87
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.95
D;D;D;.;D;D;D
M_CAP
Benign
0.022
T
MetaRNN
Benign
0.18
T;T;T;T;T;T;T
MetaSVM
Uncertain
-0.081
T
MutationAssessor
Uncertain
2.6
.;.;.;M;.;.;M
PhyloP100
7.8
PrimateAI
Uncertain
0.57
T
PROVEAN
Uncertain
-3.6
D;D;.;.;D;D;.
REVEL
Uncertain
0.38
Sift
Uncertain
0.0030
D;D;.;.;D;D;.
Polyphen
1.0
.;.;.;D;.;.;D
Vest4
0.43
MVP
0.37
MPC
0.46
ClinPred
0.25
T
GERP RS
5.8
Mutation Taster
=39/61
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs372881122; hg19: chr2-179481856; COSMIC: COSV107417805; API