rs140252432

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM5BP4_Moderate

The NM_001267550.2(TTN):​c.61814T>C​(p.Ile20605Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,613,306 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts 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. I20605V) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

3
5
8

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.29

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 0 ACMG points.

PM5
Other missense variant is known to change same aminoacid residue: Variant chr2-178589912-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1502980.
BP4
Computational evidence support a benign effect (MetaRNN=0.18288013).

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.61814T>Cp.Ile20605Thr
missense
Exon 304 of 363NP_001254479.2
TTN
NM_001256850.1
c.56891T>Cp.Ile18964Thr
missense
Exon 254 of 313NP_001243779.1
TTN
NM_133378.4
c.54110T>Cp.Ile18037Thr
missense
Exon 253 of 312NP_596869.4

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.61814T>Cp.Ile20605Thr
missense
Exon 304 of 363ENSP00000467141.1
TTN
ENST00000446966.2
TSL:1
c.61658T>Cp.Ile20553Thr
missense
Exon 302 of 361ENSP00000408004.2
TTN
ENST00000436599.2
TSL:1
c.61538T>Cp.Ile20513Thr
missense
Exon 302 of 361ENSP00000405517.2

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152070
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000194
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:
0.0000241
AC:
6
AN:
248614
AF XY:
0.0000222
show subpopulations
Gnomad AFR exome
AF:
0.000129
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000169
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000166
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461118
Hom.:
0
Cov.:
37
AF XY:
0.00
AC XY:
0
AN XY:
726858
show subpopulations
African (AFR)
AF:
0.0000897
AC:
3
AN:
33446
American (AMR)
AF:
0.00
AC:
0
AN:
44680
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26122
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39552
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86236
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53384
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111584
Other (OTH)
AF:
0.00
AC:
0
AN:
60350
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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

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:
0.0000197
AC:
3
AN:
152188
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74402
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41566
American (AMR)
AF:
0.0000654
AC:
1
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.000194
AC:
1
AN:
5146
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67968
Other (OTH)
AF:
0.00
AC:
0
AN:
2108
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
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000264
ESP6500AA
AF:
0.000271
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000331
AC:
4
Asia WGS
AF:
0.000289
AC:
1
AN:
3476

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
May 12, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.42
BayesDel_addAF
Benign
-0.20
T
BayesDel_noAF
Benign
-0.26
CADD
Benign
21
DANN
Benign
0.88
Eigen
Pathogenic
0.83
Eigen_PC
Pathogenic
0.85
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.87
D
M_CAP
Benign
0.017
T
MetaRNN
Benign
0.18
T
MetaSVM
Benign
-0.48
T
MutationAssessor
Benign
1.5
L
PhyloP100
7.3
PrimateAI
Uncertain
0.75
T
PROVEAN
Uncertain
-3.7
D
REVEL
Uncertain
0.40
Sift
Benign
0.031
D
Polyphen
1.0
D
Vest4
0.45
MVP
0.74
MPC
0.52
ClinPred
0.11
T
GERP RS
6.1
Mutation Taster
=76/24
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: rs140252432; hg19: chr2-179454638; API