2-178533251-C-T

Variant summary

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

The NM_001267550.2(TTN):​c.103364G>A​(p.Arg34455His) variant causes a missense change. The variant allele was found at a frequency of 0.0000124 in 1,613,832 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R34455C) has been classified as Benign.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

5
11

Clinical Significance

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

Conservation

PhyloP100: 6.15

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: Likely_benign. The variant received -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.11592704).

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

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
NM_001267550.2
MANE Select
c.103364G>Ap.Arg34455His
missense
Exon 358 of 363NP_001254479.2
TTN
NM_001256850.1
c.98441G>Ap.Arg32814His
missense
Exon 308 of 313NP_001243779.1
TTN
NM_133378.4
c.95660G>Ap.Arg31887His
missense
Exon 307 of 312NP_596869.4

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.103364G>Ap.Arg34455His
missense
Exon 358 of 363ENSP00000467141.1
TTN
ENST00000446966.2
TSL:1
c.103208G>Ap.Arg34403His
missense
Exon 356 of 361ENSP00000408004.2
TTN
ENST00000436599.2
TSL:1
c.103088G>Ap.Arg34363His
missense
Exon 356 of 361ENSP00000405517.2

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152158
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000965
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000193
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:
0.0000201
AC:
5
AN:
248594
AF XY:
0.0000223
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.0000996
Gnomad EAS exome
AF:
0.000111
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000103
AC:
15
AN:
1461674
Hom.:
0
Cov.:
40
AF XY:
0.0000138
AC XY:
10
AN XY:
727120
show subpopulations
African (AFR)
AF:
0.000119
AC:
4
AN:
33478
American (AMR)
AF:
0.0000224
AC:
1
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.0000383
AC:
1
AN:
26134
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39698
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53402
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1111844
Other (OTH)
AF:
0.00
AC:
0
AN:
60374
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.518
Heterozygous variant carriers
0
1
3
4
6
7
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:
152158
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74336
show subpopulations
African (AFR)
AF:
0.0000965
AC:
4
AN:
41438
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5174
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.435
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

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:
0.0000508
Hom.:
0
Bravo
AF:
0.0000340
ExAC
AF:
0.0000248
AC:
3

ClinVar

ClinVar submissions as Germline

Significance:Uncertain significance
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
1
-
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G (1)
-
1
-
Cardiomyopathy (1)
-
1
-
not provided (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.18
BayesDel_addAF
Benign
-0.18
T
BayesDel_noAF
Benign
-0.27
CADD
Benign
20
DANN
Benign
0.94
Eigen
Benign
-0.045
Eigen_PC
Benign
0.15
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.86
D
M_CAP
Benign
0.019
T
MetaRNN
Benign
0.12
T
MetaSVM
Benign
-0.90
T
MutationAssessor
Benign
0.69
N
PhyloP100
6.1
PrimateAI
Uncertain
0.53
T
PROVEAN
Uncertain
-3.5
D
REVEL
Benign
0.16
Sift
Uncertain
0.0050
D
Polyphen
0.080
B
Vest4
0.42
MVP
0.21
MPC
0.11
ClinPred
0.28
T
GERP RS
4.9
Mutation Taster
=82/18
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: rs756023873; hg19: chr2-179397978; COSMIC: COSV100588628; COSMIC: COSV100588628; API