rs376768790

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_001267550.2(TTN):​c.2686G>A​(p.Val896Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000182 in 1,614,128 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00023 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00018 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:10B:6

Conservation

PhyloP100: 0.543

Publications

12 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 -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.016604513).
BP6
Variant 2-178784159-C-T is Benign according to our data. Variant chr2-178784159-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 46839.

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.2686G>Ap.Val896Ile
missense
Exon 16 of 363NP_001254479.2Q8WZ42-12
TTN
NM_001256850.1
c.2686G>Ap.Val896Ile
missense
Exon 16 of 313NP_001243779.1Q8WZ42-1
TTN
NM_133378.4
c.2686G>Ap.Val896Ile
missense
Exon 16 of 312NP_596869.4Q8WZ42-11

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.2686G>Ap.Val896Ile
missense
Exon 16 of 363ENSP00000467141.1Q8WZ42-12
TTN
ENST00000446966.2
TSL:1
c.2686G>Ap.Val896Ile
missense
Exon 16 of 361ENSP00000408004.2A0A1B0GXE3
TTN
ENST00000436599.2
TSL:1
c.2410G>Ap.Val804Ile
missense
Exon 14 of 361ENSP00000405517.2A0A0C4DG59

Frequencies

GnomAD3 genomes
AF:
0.000230
AC:
35
AN:
152168
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000217
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000385
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000353
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000203
AC:
51
AN:
251120
AF XY:
0.000206
show subpopulations
Gnomad AFR exome
AF:
0.000308
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000194
Gnomad OTH exome
AF:
0.000490
GnomAD4 exome
AF:
0.000176
AC:
258
AN:
1461842
Hom.:
0
Cov.:
31
AF XY:
0.000172
AC XY:
125
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.000209
AC:
7
AN:
33476
American (AMR)
AF:
0.0000671
AC:
3
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000383
AC:
1
AN:
26136
East Asian (EAS)
AF:
0.0000756
AC:
3
AN:
39688
South Asian (SAS)
AF:
0.000672
AC:
58
AN:
86256
European-Finnish (FIN)
AF:
0.0000374
AC:
2
AN:
53420
Middle Eastern (MID)
AF:
0.00121
AC:
7
AN:
5768
European-Non Finnish (NFE)
AF:
0.000148
AC:
165
AN:
1111984
Other (OTH)
AF:
0.000199
AC:
12
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
Heterozygous variant carriers
0
19
39
58
78
97
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.000230
AC:
35
AN:
152286
Hom.:
0
Cov.:
32
AF XY:
0.000188
AC XY:
14
AN XY:
74468
show subpopulations
African (AFR)
AF:
0.000217
AC:
9
AN:
41546
American (AMR)
AF:
0.00
AC:
0
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000386
AC:
2
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000353
AC:
24
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.498
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:
0.000115
Hom.:
0
Bravo
AF:
0.000185
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.000214
AC:
26
Asia WGS
AF:
0.000289
AC:
1
AN:
3476
EpiCase
AF:
0.000436
EpiControl
AF:
0.000356

ClinVar

ClinVar submissions
Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
4
-
not provided (4)
-
-
3
not specified (3)
-
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
-
Cardiomyopathy (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
Tibial muscular dystrophy (1)
-
1
-
TTN-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.056
BayesDel_addAF
Benign
-0.56
T
BayesDel_noAF
Benign
-0.68
CADD
Benign
10
DANN
Benign
0.88
Eigen
Benign
-1.0
Eigen_PC
Benign
-0.85
FATHMM_MKL
Benign
0.067
N
LIST_S2
Benign
0.66
T
M_CAP
Benign
0.064
D
MetaRNN
Benign
0.017
T
MetaSVM
Benign
-1.0
T
PhyloP100
0.54
PrimateAI
Benign
0.26
T
PROVEAN
Benign
0.090
N
REVEL
Benign
0.097
Sift
Benign
0.64
T
Sift4G
Benign
1.0
T
Polyphen
0.0
B
Vest4
0.092
MVP
0.099
MPC
0.068
ClinPred
0.0094
T
GERP RS
1.8
Mutation Taster
=81/19
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: rs376768790; hg19: chr2-179648886; COSMIC: COSV59930585; COSMIC: COSV59930585; API