rs368538884

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BP4_Strong

The NM_001267550.2(TTN):​c.31762+4C>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 0.0000901 in 1,609,636 control chromosomes in the GnomAD database, including 1 homozygotes. 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000094 ( 1 hom. )

Consequence

TTN
NM_001267550.2 splice_region, intron

Scores

2
Splicing: ADA: 0.00002633
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:1

Conservation

PhyloP100: 0.0440
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.78).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTNNM_001267550.2 linkuse as main transcriptc.31762+4C>T splice_region_variant, intron_variant ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkuse as main transcriptc.31762+4C>T splice_region_variant, intron_variant 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152064
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000193
Gnomad SAS
AF:
0.000414
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000931
AC:
23
AN:
246920
Hom.:
0
AF XY:
0.000119
AC XY:
16
AN XY:
133986
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 SAS exome
AF:
0.000531
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000623
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000940
AC:
137
AN:
1457454
Hom.:
1
Cov.:
30
AF XY:
0.0000842
AC XY:
61
AN XY:
724862
show subpopulations
Gnomad4 AFR exome
AF:
0.0000301
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.000304
Gnomad4 FIN exome
AF:
0.0000188
Gnomad4 NFE exome
AF:
0.0000937
Gnomad4 OTH exome
AF:
0.0000831
GnomAD4 genome
AF:
0.0000526
AC:
8
AN:
152182
Hom.:
0
Cov.:
32
AF XY:
0.0000672
AC XY:
5
AN XY:
74398
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000193
Gnomad4 SAS
AF:
0.000415
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000735
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000847
Hom.:
0
Bravo
AF:
0.0000416
Asia WGS
AF:
0.000866
AC:
3
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineMay 08, 2014The 28030+4C>T variant in TTN has not been previously reported in individuals wi th cardiomyopathy, but has been identified in 1/8250 European American chromosom es by the NHLBI Exome Sequencing Project (http://evs.gs.washington.edu; dbSNP rs 368538884). This variant is located in the 5' splice region. Computational tool s do not suggest an effect on splicing; however, this information is not predict ive enough to rule out pathogenicity. In summary, the clinical significance of t he 28030+4C>T variant is uncertain. -
Uncertain significance, criteria provided, single submitterclinical testingGenetic Services Laboratory, University of ChicagoMar 04, 2016- -
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpApr 06, 2017- -
Cardiomyopathy Benign:1
Likely benign, criteria provided, single submitterclinical testingCHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern OntarioAug 11, 2020- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.78
CADD
Benign
12
DANN
Benign
0.58

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.000026
dbscSNV1_RF
Benign
0.0080
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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs368538884; hg19: chr2-179556739; API