chr2-178676009-A-G

Position:

chr2-178676009-A-G

Variant summary

Our verdict is Benign. Variant got -10 ACMG points: 0P and 10B. BP4_ModerateBP6_Very_Strong

The NM_001267550.2(TTN):c.34379-14T>C variant causes a splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000024 in 1,583,034 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 Likely benign (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

TTN
NM_001267550.2 splice_polypyrimidine_tract, intron

Scores

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:7

Conservation

PhyloP100: 0.932

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 links:

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]

TTN-AS1 links:

LOC124906100 (HGNC:):

LOC124906100 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -10 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.3).

BP6

Variant 2-178676009-A-G is Benign according to our data. Variant chr2-178676009-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 180090.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TTN	NM_001267550.2 linkuse as main transcript	c.34379-14T>C		splice_polypyrimidine_tract_variant, intron_variant		ENST00000589042.5	NP_001254479.2
LOC124906100	XR_007087318.1 linkuse as main transcript	n.2185+31508A>G		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TTN	ENST00000589042.5 linkuse as main transcript	c.34379-14T>C		splice_polypyrimidine_tract_variant, intron_variant		5	NM_001267550.2	ENSP00000467141	P1
TTN-AS1	ENST00000659121.1 linkuse as main transcript	n.503-58495A>G		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

151840

Hom.:

Cov.:

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:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000442

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000447

AC:

AN:

201174

Hom.:

AF XY:

0.0000559

AC XY:

AN XY:

107256

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000104

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000670

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000465

Gnomad OTH exome

AF:

0.000195

GnomAD4 exome

AF:

0.0000231

AC:

AN:

1431194

Hom.:

Cov.:

AF XY:

0.0000254

AC XY:

AN XY:

708958

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000750

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000256

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000219

Gnomad4 OTH exome

AF:

0.0000506

GnomAD4 genome

AF:

0.0000329

AC:

AN:

151840

Hom.:

Cov.:

AF XY:

0.0000270

AC XY:

AN XY:

74144

show subpopulations

Gnomad4 AFR

AF:

0.0000483

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000442

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000130

Hom.:

Bravo

AF:

0.0000227

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Nov 24, 2014

c.30560-14T>C in intron 143 of TTN: This variant is not expected to have clinica l significance because a T>C change at this position does not diverge from the s plice consensus sequence and is therefore unlikely to impact splicing. -

Autosomal recessive limb-girdle muscular dystrophy type 2J

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Sep 10, 2021

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 10, 2024

- -

Early-onset myopathy with fatal cardiomyopathy

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Sep 10, 2021

- -

not provided

Benign:1

Benign, criteria provided, single submitter

clinical testing

GeneDx

May 11, 2015

- -

Tibial muscular dystrophy

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Sep 10, 2021

- -

Myopathy, myofibrillar, 9, with early respiratory failure

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Sep 10, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.30

CADD

Benign

DANN

Benign

0.80

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

LitVar

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

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over