rs370300135

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_001267550.2(TTN):​c.100049C>T​(p.Thr33350Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000453 in 1,613,192 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). Synonymous variant affecting the same amino acid position (i.e. T33350T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00016 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000033 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

3
5
9

Clinical Significance

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

Conservation

PhyloP100: 8.04

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 -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.04560283).
BP6
Variant 2-178537060-G-A is Benign according to our data. Variant chr2-178537060-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 404664.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.100049C>T p.Thr33350Ile missense_variant Exon 356 of 363 ENST00000589042.5 NP_001254479.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.100049C>T p.Thr33350Ile missense_variant Exon 356 of 363 5 NM_001267550.2 ENSP00000467141.1

Frequencies

GnomAD3 genomes
AF:
0.000164
AC:
25
AN:
152168
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000386
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00173
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:
0.000113
AC:
28
AN:
247516
AF XY:
0.000104
show subpopulations
Gnomad AFR exome
AF:
0.000261
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00135
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000329
AC:
48
AN:
1460906
Hom.:
0
Cov.:
32
AF XY:
0.0000317
AC XY:
23
AN XY:
726686
show subpopulations
African (AFR)
AF:
0.000120
AC:
4
AN:
33448
American (AMR)
AF:
0.00
AC:
0
AN:
44626
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26104
East Asian (EAS)
AF:
0.000757
AC:
30
AN:
39630
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86144
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53324
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111530
Other (OTH)
AF:
0.000166
AC:
10
AN:
60332
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
3
7
10
14
17
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:
0.000164
AC:
25
AN:
152286
Hom.:
0
Cov.:
33
AF XY:
0.000148
AC XY:
11
AN XY:
74462
show subpopulations
African (AFR)
AF:
0.000385
AC:
16
AN:
41552
American (AMR)
AF:
0.00
AC:
0
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00174
AC:
9
AN:
5178
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
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:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.507
Heterozygous variant carriers
0
2
3
5
6
8
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:
0.000285
Hom.:
0
Bravo
AF:
0.000238
ESP6500AA
AF:
0.000258
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000910
AC:
11
Asia WGS
AF:
0.000866
AC:
3
AN:
3478

ClinVar

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

Submissions by phenotype

not provided Uncertain:2Benign:1
Jan 04, 2020
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 07, 2017
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 14, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 31983221, 26062443) -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Mar 14, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiomyopathy Benign:1
Feb 11, 2018
Center for Advanced Laboratory Medicine, UC San Diego Health, University of California San Diego
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Benign:1
Aug 17, 2020
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.52
BayesDel_addAF
Benign
-0.28
T
BayesDel_noAF
Benign
-0.22
CADD
Benign
21
DANN
Benign
0.90
Eigen
Pathogenic
0.74
Eigen_PC
Pathogenic
0.74
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.83
T;T;T;.;T;T;T
M_CAP
Benign
0.032
D
MetaRNN
Benign
0.046
T;T;T;T;T;T;T
MetaSVM
Benign
-0.30
T
MutationAssessor
Benign
1.8
.;.;.;L;.;.;L
PhyloP100
8.0
PrimateAI
Uncertain
0.57
T
PROVEAN
Uncertain
-4.0
D;D;.;.;D;D;.
REVEL
Uncertain
0.38
Sift
Uncertain
0.017
D;T;.;.;T;T;.
Polyphen
0.95
.;.;.;P;.;.;P
Vest4
0.57
MVP
0.59
MPC
0.37
ClinPred
0.13
T
GERP RS
4.6
Mutation Taster
=72/28
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: rs370300135; hg19: chr2-179401787; API