2-178698916-TAAAAAAAAA-TAAAAAA

Position:

• chr2-178698916-TAAAAAAAAA-TAAAAAA

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 0P and 0B.

The NM_001267550.2(TTN):​c.30683-5_30683-3del variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000833 in 1,218,420 control chromosomes in the GnomAD database, with no homozygous occurrence. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0 (0 hom., cov: 30)
  • Exomes 𝑓: 0.00083 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: TTN NM_001267550.2 splice_region, splice_polypyrimidine_tract, intron
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.01

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]

LOC124906100 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTN	NM_001267550.2	c.30683-5_30683-3del		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000589042.5
LOC124906100	XR_007087318.1	n.2186-14825_2186-14823del		intron_variant, non_coding_transcript_variant
LOC124907912	XR_007087321.1	n.7314+3478_7314+3480del		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTN	ENST00000589042.5	c.30683-5_30683-3del		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		5	NM_001267550.2	P1
TTN-AS1	ENST00000659121.1	n.503-35575_503-35573del		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes AF: 0.00 AC: 0 AN: 85092 Hom.: 0 Cov.: 30 FAILED QC

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

GnomAD3 exomes AF: 0.00410 AC: 270 AN: 65808 Hom.: 0 AF XY: 0.00408 AC XY: 146 AN XY: 35820

Gnomad AFR exome AF: 0.00279

Gnomad AMR exome AF: 0.00839

Gnomad ASJ exome AF: 0.00373

Gnomad EAS exome AF: 0.00479

Gnomad SAS exome AF: 0.00285

Gnomad FIN exome AF: 0.00453

Gnomad NFE exome AF: 0.00352

Gnomad OTH exome AF: 0.00396

GnomAD4 exome AF: 0.000833 AC: 1015 AN: 1218420 Hom.: 0 AF XY: 0.000887 AC XY: 533 AN XY: 600976

Gnomad4 AFR exome AF: 0.000815

Gnomad4 AMR exome AF: 0.00330

Gnomad4 ASJ exome AF: 0.00152

Gnomad4 EAS exome AF: 0.00109

Gnomad4 SAS exome AF: 0.00195

Gnomad4 FIN exome AF: 0.00168

Gnomad4 NFE exome AF: 0.000657

Gnomad4 OTH exome AF: 0.000947

GnomAD4 genome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 85092 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 40596

Gnomad4 AFR AF: 0.00

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: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Eurofins Ntd Llc (ga)

Jul 20, 2015

- -

Computational scores

Source: dbNSFP v4.3

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

Other links and lift over

dbSNP: rs368277751; hg19: chr2-179563643;