2-178735784-G-C

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4BP6

The NM_001267550.2(TTN):​c.14662C>G​(p.Pro4888Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000139 in 1,613,594 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00015 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

4
4
8

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:2

Conservation

PhyloP100: 9.92

Publications

1 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=0.32252425).
BP6
Variant 2-178735784-G-C is Benign according to our data. Variant chr2-178735784-G-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 203239.We mark this variant Likely_benign, oryginal submission is: [Conflicting_classifications_of_pathogenicity].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.14662C>G p.Pro4888Ala missense_variant Exon 50 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.14662C>G p.Pro4888Ala missense_variant Exon 50 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152150
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.0000943
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000564
AC:
14
AN:
248336
AF XY:
0.0000594
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000465
Gnomad NFE exome
AF:
0.000116
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000148
AC:
216
AN:
1461444
Hom.:
0
Cov.:
30
AF XY:
0.000127
AC XY:
92
AN XY:
726990
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44710
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39630
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.0000562
AC:
3
AN:
53366
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.000187
AC:
208
AN:
1111766
Other (OTH)
AF:
0.0000829
AC:
5
AN:
60346
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.457
Heterozygous variant carriers
0
12
24
37
49
61
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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.:
33
AF XY:
0.0000404
AC XY:
3
AN XY:
74314
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41442
American (AMR)
AF:
0.00
AC:
0
AN:
15258
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.0000943
AC:
1
AN:
10600
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000745
Hom.:
0
Bravo
AF:
0.0000416
TwinsUK
AF:
0.00108
AC:
4
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000122
AC:
1
ExAC
AF:
0.0000331
AC:
4
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000296

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

TTN-related disorder Uncertain:1
Apr 02, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The TTN c.14662C>G variant is predicted to result in the amino acid substitution p.Pro4888Ala. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.011% of alleles in individuals of European (Non-Finnish) descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Dec 06, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Dec 09, 2021
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1
Feb 28, 2018
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Cardiomyopathy Benign:1
Nov 10, 2022
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.49
BayesDel_addAF
Benign
-0.065
T
BayesDel_noAF
Benign
-0.13
CADD
Benign
22
DANN
Benign
0.75
Eigen
Pathogenic
0.97
Eigen_PC
Pathogenic
0.88
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Benign
0.80
T;T;.;T
M_CAP
Benign
0.064
D
MetaRNN
Benign
0.32
T;T;T;T
MetaSVM
Uncertain
0.68
D
PhyloP100
9.9
PrimateAI
Uncertain
0.53
T
PROVEAN
Uncertain
-4.3
D;.;.;.
REVEL
Pathogenic
0.69
Sift
Benign
0.27
T;.;.;.
Polyphen
1.0
.;.;D;D
Vest4
0.20
MVP
0.68
MPC
0.46
ClinPred
0.14
T
GERP RS
5.8
Mutation Taster
=13/87
disease causing

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: rs376799249; hg19: chr2-179600511; API