2-178578174-C-T

Variant names:

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PP3

The NM_001267550.2(TTN):c.68341G>A(p.Glu22781Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000161 in 1,611,394 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. E22781E) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 7.86

Publications

1 publications found

Variant links:

COSMIC-nc: COSV60092919

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:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.789

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001267550.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
TTN	NM_001267550.2	MANE Select	c.68341G>A	p.Glu22781Lys	missense	Exon 322 of 363	NP_001254479.2
TTN	NM_001256850.1		c.63418G>A	p.Glu21140Lys	missense	Exon 272 of 313	NP_001243779.1
TTN	NM_133378.4		c.60637G>A	p.Glu20213Lys	missense	Exon 271 of 312	NP_596869.4

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
TTN	ENST00000589042.5	TSL:5 MANE Select	c.68341G>A	p.Glu22781Lys	missense	Exon 322 of 363	ENSP00000467141.1
TTN	ENST00000446966.2	TSL:1	c.68185G>A	p.Glu22729Lys	missense	Exon 320 of 361	ENSP00000408004.2
TTN	ENST00000436599.2	TSL:1	c.68065G>A	p.Glu22689Lys	missense	Exon 320 of 361	ENSP00000405517.2

Frequencies

GnomAD3 genomes

AF:

0.0000460

AC:

AN:

152014

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000966

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:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000162

AC:

AN:

246786

AF XY:

0.0000224

show subpopulations

Gnomad AFR exome

AF:

0.0000647

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.0000486

Gnomad NFE exome

AF:

0.0000178

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000130

AC:

AN:

1459380

Hom.:

Cov.:

AF XY:

0.0000152

AC XY:

AN XY:

726028

show subpopulations

African (AFR)

AF:

0.0000898

AC:

AN:

33398

American (AMR)

AF:

0.00

AC:

AN:

44622

Ashkenazi Jewish (ASJ)

AF:

0.0000767

AC:

AN:

26086

East Asian (EAS)

AF:

0.00

AC:

AN:

39614

South Asian (SAS)

AF:

0.0000348

AC:

AN:

86098

European-Finnish (FIN)

AF:

0.0000191

AC:

AN:

52248

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5746

European-Non Finnish (NFE)

AF:

0.00000630

AC:

AN:

1111258

Other (OTH)

AF:

0.0000497

AC:

AN:

60310

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.493

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.0000460

AC:

AN:

152014

Hom.:

Cov.:

AF XY:

0.0000674

AC XY:

AN XY:

74234

show subpopulations

African (AFR)

AF:

0.0000966

AC:

AN:

41410

American (AMR)

AF:

0.00

AC:

AN:

15262

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5164

South Asian (SAS)

AF:

0.00

AC:

AN:

4824

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10604

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000441

AC:

AN:

67960

Other (OTH)

AF:

0.00

AC:

AN:

2092

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.482

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.000152

Hom.:

Bravo

AF:

0.0000340

ExAC

AF:

0.00000828

AC:

EpiCase

AF:

0.0000546

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

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

Uncertain:1

Aug 03, 2016

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

not provided

Uncertain:1

Apr 22, 2024

Revvity Omics, Revvity

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.98

BayesDel_addAF

Benign

-0.045

BayesDel_noAF

Benign

-0.12

CADD

Benign

(source)

DANN

Benign

0.97

Eigen

Pathogenic

0.95

Eigen_PC

Pathogenic

0.86

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.97

M_CAP

Benign

0.024

MetaRNN

Pathogenic

0.79

MetaSVM

Uncertain

0.13

MutationAssessor

Pathogenic

3.7

PhyloP100

7.9

PrimateAI

Uncertain

0.75

PROVEAN

Uncertain

-3.2

REVEL

Uncertain

0.52

Sift

Uncertain

0.0040

Polyphen

1.0

Vest4

0.65

MutPred

0.70

Gain of MoRF binding (P = 0.0058)

MVP

0.38

MPC

0.49

ClinPred

0.88

GERP RS

5.6

Mutation Taster

=94/6

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over