chr2-178733497-G-A

Variant names:

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PVS1PP5

The NM_001267550.2(TTN):c.15796C>T(p.Arg5266*) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000745 in 1,610,296 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 Conflicting classifications of pathogenicity (no stars). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000069 ( 0 hom. )

Consequence

TTN
NM_001267550.2 stop_gained

Scores

Clinical Significance

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

Conservation

PhyloP100: 3.86

Publications

1 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 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: Likely_pathogenic. The variant received 9 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PP5

Variant 2-178733497-G-A is Pathogenic according to our data. Variant chr2-178733497-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 130662.

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	UniProt
TTN	NM_001267550.2	MANE Select	c.15796C>T	p.Arg5266*	stop_gained	Exon 54 of 363	NP_001254479.2	Q8WZ42-12
TTN	NM_001256850.1		c.14845C>T	p.Arg4949*	stop_gained	Exon 52 of 313	NP_001243779.1	Q8WZ42-1
TTN	NM_133378.4		c.12064C>T	p.Arg4022*	stop_gained	Exon 51 of 312	NP_596869.4	Q8WZ42-11

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
TTN	ENST00000589042.5	TSL:5 MANE Select	c.15796C>T	p.Arg5266*	stop_gained	Exon 54 of 363	ENSP00000467141.1	Q8WZ42-12
TTN	ENST00000446966.2	TSL:1	c.15796C>T	p.Arg5266*	stop_gained	Exon 54 of 361	ENSP00000408004.2	A0A1B0GXE3
TTN	ENST00000436599.2	TSL:1	c.15520C>T	p.Arg5174*	stop_gained	Exon 52 of 361	ENSP00000405517.2	A0A0C4DG59

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152110

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.00000405

AC:

AN:

246696

AF XY:

0.00

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:

0.00

Gnomad NFE exome

AF:

0.00000896

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000686

AC:

AN:

1458186

Hom.:

Cov.:

AF XY:

0.00000552

AC XY:

AN XY:

724876

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33304

American (AMR)

AF:

0.00

AC:

AN:

44432

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26040

East Asian (EAS)

AF:

0.00

AC:

AN:

39636

South Asian (SAS)

AF:

0.0000116

AC:

AN:

85926

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53248

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5750

European-Non Finnish (NFE)

AF:

0.00000811

AC:

AN:

1109638

Other (OTH)

AF:

0.00

AC:

AN:

60212

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.480

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:

0.0000131

AC:

AN:

152110

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74306

show subpopulations

African (AFR)

AF:

0.0000241

AC:

AN:

41412

American (AMR)

AF:

0.00

AC:

AN:

15264

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5190

South Asian (SAS)

AF:

0.00

AC:

AN:

4828

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10606

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

68016

Other (OTH)

AF:

0.00

AC:

AN:

2094

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.450

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome 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

Alfa

AF:

0.0000215

Hom.:

Bravo

AF:

0.0000189

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000121

AC:

ExAC

AF:

0.00000827

AC:

ClinVar

ClinVar submissions

Significance:Conflicting classifications of pathogenicity

Revision:criteria provided, conflicting classifications

View on ClinVar

Pathogenic

VUS

Benign

Condition

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

not provided (1)

Orofacial cleft 1 (1)

Tibial muscular dystrophy (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.58

BayesDel_noAF

Pathogenic

0.60

CADD

Pathogenic

(source)

DANN

Uncertain

0.99

Eigen

Pathogenic

0.79

Eigen_PC

Uncertain

0.59

FATHMM_MKL

Uncertain

0.92

PhyloP100

3.9

Vest4

0.97

GERP RS

1.1

Mutation Taster

=0/200

disease causing (ClinVar)

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over