rs375343798

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2BP4_StrongBP6

The NM_001267550.2(TTN):​c.54812-5A>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000303 in 1,321,872 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (no stars).

Frequency

Genomes: 𝑓 0.0 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000030 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

TTN
NM_001267550.2 splice_region, intron

Scores

2
Splicing: ADA: 0.00001965
2

Clinical Significance

Likely benign no assertion criteria provided B:2

Conservation

PhyloP100: 0.349

Publications

0 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 -3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.85).
BP6
Variant 2-178602595-T-A is Benign according to our data. Variant chr2-178602595-T-A is described in ClinVar as Likely_benign. ClinVar VariationId is 1328294.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.54812-5A>T splice_region_variant, intron_variant Intron 282 of 362 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.54812-5A>T splice_region_variant, intron_variant Intron 282 of 362 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.00
AC:
0
AN:
151102
Hom.:
0
Cov.:
32
Gnomad AFR
AF:
0.00
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:
0.0000408
AC:
4
AN:
98144
AF XY:
0.0000589
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:
0.0000761
Gnomad NFE exome
AF:
0.0000476
Gnomad OTH exome
AF:
0.000388
GnomAD4 exome
AF:
0.00000303
AC:
4
AN:
1321872
Hom.:
0
Cov.:
32
AF XY:
0.00000465
AC XY:
3
AN XY:
645780
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
28276
American (AMR)
AF:
0.00
AC:
0
AN:
19552
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
20574
East Asian (EAS)
AF:
0.00
AC:
0
AN:
35064
South Asian (SAS)
AF:
0.00
AC:
0
AN:
64938
European-Finnish (FIN)
AF:
0.0000213
AC:
1
AN:
46998
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5232
European-Non Finnish (NFE)
AF:
0.00000191
AC:
2
AN:
1046748
Other (OTH)
AF:
0.0000184
AC:
1
AN:
54490
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.225
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Data not reliable, filtered out with message: AC0;AS_VQSR
AF:
0.00
AC:
0
AN:
151102
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
73720
African (AFR)
AF:
0.00
AC:
0
AN:
41146
American (AMR)
AF:
0.00
AC:
0
AN:
15162
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5100
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4788
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10404
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67734
Other (OTH)
AF:
0.00
AC:
0
AN:
2070

ClinVar

Significance: Likely benign
Submissions summary: Benign:2
Revision: no assertion criteria provided
LINK: link

Submissions by phenotype

not provided Benign:2
-
Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.85
CADD
Benign
1.2
DANN
Benign
0.64
PhyloP100
0.35

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.000020
dbscSNV1_RF
Benign
0.038
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: rs375343798; hg19: chr2-179467322; API