2-178729324-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PP3

The NM_001267550.2(TTN):​c.18832G>A​(p.Gly6278Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000161 in 1,611,912 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000017 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

5
3
7

Clinical Significance

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

Conservation

PhyloP100: 7.91

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.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.772

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.18832G>Ap.Gly6278Ser
missense
Exon 64 of 363NP_001254479.2
TTN
NM_001256850.1
c.17881G>Ap.Gly5961Ser
missense
Exon 62 of 313NP_001243779.1
TTN
NM_133378.4
c.15100G>Ap.Gly5034Ser
missense
Exon 61 of 312NP_596869.4

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.18832G>Ap.Gly6278Ser
missense
Exon 64 of 363ENSP00000467141.1
TTN
ENST00000446966.2
TSL:1
c.18832G>Ap.Gly6278Ser
missense
Exon 64 of 361ENSP00000408004.2
TTN
ENST00000436599.2
TSL:1
c.18556G>Ap.Gly6186Ser
missense
Exon 62 of 361ENSP00000405517.2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152112
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000162
AC:
4
AN:
247456
AF XY:
0.0000149
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000167
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000167
GnomAD4 exome
AF:
0.0000171
AC:
25
AN:
1459800
Hom.:
0
Cov.:
33
AF XY:
0.0000152
AC XY:
11
AN XY:
725880
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33430
American (AMR)
AF:
0.00
AC:
0
AN:
44660
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26076
East Asian (EAS)
AF:
0.000177
AC:
7
AN:
39652
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86124
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53356
Middle Eastern (MID)
AF:
0.000174
AC:
1
AN:
5752
European-Non Finnish (NFE)
AF:
0.0000117
AC:
13
AN:
1110476
Other (OTH)
AF:
0.0000332
AC:
2
AN:
60274
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.493
Heterozygous variant carriers
0
2
4
6
8
10
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:
0.00000657
AC:
1
AN:
152112
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74288
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41420
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68018
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000227
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000546
EpiControl
AF:
0.00

ClinVar

ClinVar submissions as Germline
Significance:Uncertain significance
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
2
-
not specified (2)
-
1
-
TTN-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.46
BayesDel_addAF
Benign
-0.13
T
BayesDel_noAF
Benign
-0.16
CADD
Benign
23
DANN
Benign
0.87
Eigen
Pathogenic
0.87
Eigen_PC
Pathogenic
0.79
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Benign
0.84
T
M_CAP
Benign
0.038
D
MetaRNN
Pathogenic
0.77
D
MetaSVM
Uncertain
0.46
D
PhyloP100
7.9
PrimateAI
Benign
0.43
T
PROVEAN
Uncertain
-3.2
D
REVEL
Pathogenic
0.65
Sift
Benign
0.081
T
Polyphen
1.0
D
Vest4
0.45
MutPred
0.88
Gain of disorder (P = 0.0429)
MVP
0.51
MPC
0.46
ClinPred
0.21
T
GERP RS
5.9
Mutation Taster
=61/39
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: rs397517488; hg19: chr2-179594051; COSMIC: COSV60391499; COSMIC: COSV60391499; API