rs34337578

Variant summary

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

The NM_001267550.2(TTN):​c.1447G>A​(p.Ala483Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000489 in 1,613,964 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. A483A) has been classified as Benign.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000051 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:10B:2

Conservation

PhyloP100: 0.905

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 Gene-Disease associations (from GenCC):
  • dilated cardiomyopathy
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • dilated cardiomyopathy 1G
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • early-onset myopathy with fatal cardiomyopathy
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Labcorp Genetics (formerly Invitae)
  • TTN-related myopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • myopathy, myofibrillar, 9, with early respiratory failure
    Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Orphanet, ClinGen, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • tibial muscular dystrophy
    Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: ClinGen, Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • autosomal recessive limb-girdle muscular dystrophy type 2J
    Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae)
  • familial isolated dilated cardiomyopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • autosomal recessive centronuclear myopathy
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • childhood-onset progressive contractures-limb-girdle weakness-muscle dystrophy syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • congenital myopathy
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • hereditary skeletal muscle disorder
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • hypertrophic cardiomyopathy
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen
  • hypertrophic cardiomyopathy 9
    Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
  • arrhythmogenic right ventricular cardiomyopathy
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

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=0.11271644).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001267550.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
NM_001267550.2
MANE Select
c.1447G>Ap.Ala483Thr
missense
Exon 9 of 363NP_001254479.2Q8WZ42-12
TTN
NM_001256850.1
c.1447G>Ap.Ala483Thr
missense
Exon 9 of 313NP_001243779.1Q8WZ42-1
TTN
NM_133378.4
c.1447G>Ap.Ala483Thr
missense
Exon 9 of 312NP_596869.4Q8WZ42-11

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.1447G>Ap.Ala483Thr
missense
Exon 9 of 363ENSP00000467141.1Q8WZ42-12
TTN
ENST00000446966.2
TSL:1
c.1447G>Ap.Ala483Thr
missense
Exon 9 of 361ENSP00000408004.2A0A1B0GXE3
TTN
ENST00000436599.2
TSL:1
c.1447G>Ap.Ala483Thr
missense
Exon 9 of 361ENSP00000405517.2A0A0C4DG59

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152164
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000477
AC:
12
AN:
251352
AF XY:
0.0000589
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.0000992
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000704
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000506
AC:
74
AN:
1461800
Hom.:
0
Cov.:
31
AF XY:
0.0000536
AC XY:
39
AN XY:
727214
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000447
AC:
2
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.000115
AC:
3
AN:
26136
East Asian (EAS)
AF:
0.0000756
AC:
3
AN:
39688
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53366
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000540
AC:
60
AN:
1111990
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.453
Heterozygous variant carriers
0
5
10
16
21
26
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:
0.0000329
AC:
5
AN:
152164
Hom.:
0
Cov.:
33
AF XY:
0.0000404
AC XY:
3
AN XY:
74342
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41430
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10596
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
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:
0.0000670
Hom.:
0
Bravo
AF:
0.0000340
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.000218
EpiControl
AF:
0.000119

ClinVar

ClinVar submissions
Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
3
1
not provided (4)
-
1
-
Autosomal recessive limb-girdle muscular dystrophy type 2J (1)
-
1
-
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G (1)
-
1
-
Cardiovascular phenotype (1)
-
1
-
Dilated cardiomyopathy 1G (1)
-
1
-
Early-onset myopathy with fatal cardiomyopathy (1)
-
1
-
Myopathy, myofibrillar, 9, with early respiratory failure (1)
-
-
1
not specified (1)
-
1
-
Tibial muscular dystrophy (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.080
BayesDel_addAF
Benign
-0.28
T
BayesDel_noAF
Benign
-0.45
CADD
Benign
18
DANN
Benign
0.93
Eigen
Benign
-0.067
Eigen_PC
Benign
0.071
FATHMM_MKL
Benign
0.57
D
LIST_S2
Benign
0.80
T
M_CAP
Benign
0.027
D
MetaRNN
Benign
0.11
T
MetaSVM
Benign
-1.0
T
PhyloP100
0.91
PrimateAI
Benign
0.36
T
PROVEAN
Benign
-1.9
N
REVEL
Benign
0.039
Sift
Benign
0.35
T
Sift4G
Benign
0.11
T
Polyphen
0.015
B
Vest4
0.30
MutPred
0.30
Gain of glycosylation at A483 (P = 0.0221)
MVP
0.10
MPC
0.082
ClinPred
0.081
T
GERP RS
4.7
Mutation Taster
=77/23
polymorphism

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: rs34337578; hg19: chr2-179658220; API