2-178543858-C-T

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4_ModerateBP6

The NM_001267550.2(TTN):​c.96286G>A​(p.Ala32096Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000378 in 1,613,556 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A32096G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000036 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

6
10

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:2

Conservation

PhyloP100: 3.31

Publications

4 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 -3 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.22199097).
BP6
Variant 2-178543858-C-T is Benign according to our data. Variant chr2-178543858-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 47569.

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.96286G>Ap.Ala32096Thr
missense
Exon 346 of 363NP_001254479.2Q8WZ42-12
TTN
NM_001256850.1
c.91363G>Ap.Ala30455Thr
missense
Exon 296 of 313NP_001243779.1Q8WZ42-1
TTN
NM_133378.4
c.88582G>Ap.Ala29528Thr
missense
Exon 295 of 312NP_596869.4Q8WZ42-11

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.96286G>Ap.Ala32096Thr
missense
Exon 346 of 363ENSP00000467141.1Q8WZ42-12
TTN
ENST00000446966.2
TSL:1
c.96130G>Ap.Ala32044Thr
missense
Exon 344 of 361ENSP00000408004.2A0A1B0GXE3
TTN
ENST00000436599.2
TSL:1
c.96010G>Ap.Ala32004Thr
missense
Exon 344 of 361ENSP00000405517.2A0A0C4DG59

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152150
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000196
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:
0.0000441
Gnomad OTH
AF:
0.000958
GnomAD2 exomes
AF:
0.0000806
AC:
20
AN:
248148
AF XY:
0.0000669
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000174
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000125
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000363
AC:
53
AN:
1461406
Hom.:
0
Cov.:
33
AF XY:
0.0000330
AC XY:
24
AN XY:
726984
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33454
American (AMR)
AF:
0.000201
AC:
9
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26124
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39684
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53384
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.0000378
AC:
42
AN:
1111680
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60352
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
6
11
17
22
28
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:
0.0000526
AC:
8
AN:
152150
Hom.:
0
Cov.:
32
AF XY:
0.0000673
AC XY:
5
AN XY:
74326
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41448
American (AMR)
AF:
0.000196
AC:
3
AN:
15278
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:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68008
Other (OTH)
AF:
0.000958
AC:
2
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.412
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:
0.0000676
Hom.:
0
Bravo
AF:
0.0000680
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000243
AC:
2
ExAC
AF:
0.0000662
AC:
8
EpiCase
AF:
0.00
EpiControl
AF:
0.000296

ClinVar

ClinVar submissions
Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
2
-
not provided (2)
-
1
1
not specified (2)
-
1
-
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 (1)
-
1
-
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G (1)
-
-
1
Cardiovascular phenotype (1)
-
1
-
TTN-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Benign
-0.21
T
BayesDel_noAF
Benign
-0.29
CADD
Benign
21
DANN
Benign
0.97
Eigen
Uncertain
0.35
Eigen_PC
Uncertain
0.47
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.87
D
M_CAP
Benign
0.027
D
MetaRNN
Benign
0.22
T
MetaSVM
Benign
-0.54
T
MutationAssessor
Benign
1.1
L
PhyloP100
3.3
PrimateAI
Uncertain
0.59
T
PROVEAN
Uncertain
-2.4
N
REVEL
Benign
0.25
Sift
Benign
0.14
T
Polyphen
0.58
P
Vest4
0.47
MVP
0.42
MPC
0.13
ClinPred
0.11
T
GERP RS
6.1
Mutation Taster
=72/28
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: rs376039623; hg19: chr2-179408585; COSMIC: COSV60440909; COSMIC: COSV60440909; API