2-178749850-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_133379.5(TTN):​c.12550G>A​(p.Gly4184Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000434 in 1,613,124 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G4184C) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

TTN
NM_133379.5 missense

Scores

7
5
2

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 7.41

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: Uncertain_significance. The variant received 2 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.919

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_133379.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
NM_001267550.2
MANE Select
c.11311+3274G>A
intron
N/ANP_001254479.2Q8WZ42-12
TTN
NM_133379.5
c.12550G>Ap.Gly4184Ser
missense
Exon 46 of 46NP_596870.2Q8WZ42-6
TTN
NM_001256850.1
c.10360+3274G>A
intron
N/ANP_001243779.1Q8WZ42-1

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.11311+3274G>A
intron
N/AENSP00000467141.1Q8WZ42-12
TTN
ENST00000446966.2
TSL:1
c.11311+3274G>A
intron
N/AENSP00000408004.2A0A1B0GXE3
TTN
ENST00000436599.2
TSL:1
c.11035+3274G>A
intron
N/AENSP00000405517.2A0A0C4DG59

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
151948
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000966
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:
0.0000161
AC:
4
AN:
248882
AF XY:
0.0000148
show subpopulations
Gnomad AFR exome
AF:
0.000256
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461058
Hom.:
0
Cov.:
36
AF XY:
0.00000413
AC XY:
3
AN XY:
726854
show subpopulations
African (AFR)
AF:
0.0000897
AC:
3
AN:
33438
American (AMR)
AF:
0.00
AC:
0
AN:
44620
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26108
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39634
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86244
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53352
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5760
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111562
Other (OTH)
AF:
0.00
AC:
0
AN:
60340
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000263
AC:
4
AN:
152066
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74332
show subpopulations
African (AFR)
AF:
0.0000963
AC:
4
AN:
41534
American (AMR)
AF:
0.00
AC:
0
AN:
15238
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5166
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10596
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67918
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.412
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.00
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000247
AC:
3

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.18
D
BayesDel_noAF
Pathogenic
0.31
CADD
Benign
23
DANN
Uncertain
1.0
Eigen
Pathogenic
0.86
Eigen_PC
Pathogenic
0.86
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Benign
0.60
T
M_CAP
Benign
0.055
D
MetaRNN
Pathogenic
0.92
D
MetaSVM
Uncertain
0.36
D
PhyloP100
7.4
PROVEAN
Uncertain
-2.7
D
REVEL
Pathogenic
0.78
Sift
Uncertain
0.0060
D
Sift4G
Uncertain
0.039
D
Polyphen
1.0
D
Vest4
0.79
MutPred
0.80
Loss of glycosylation at S4183 (P = 0.0391)
MVP
0.67
ClinPred
0.28
T
GERP RS
5.8
Mutation Taster
=55/45
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: rs145460295; hg19: chr2-179614577; API