2-178729692-C-T

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_ModerateBP6BP7

The NM_001267550.2(TTN):c.18561G>A(p.Ala6187Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000242 in 1,613,694 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. A6187A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000021 ( 1 hom. )

Consequence

TTN
NM_001267550.2 synonymous

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:7

Conservation

PhyloP100: -0.559

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_benign. The variant received -4 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.42).

BP6

Variant 2-178729692-C-T is Benign according to our data. Variant chr2-178729692-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 228062.

BP7

Synonymous conserved (PhyloP=-0.559 with no splicing effect.

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.18561G>A	p.Ala6187Ala	synonymous	Exon 63 of 363	NP_001254479.2
TTN	NM_001256850.1		c.17610G>A	p.Ala5870Ala	synonymous	Exon 61 of 313	NP_001243779.1
TTN	NM_133378.4		c.14829G>A	p.Ala4943Ala	synonymous	Exon 60 of 312	NP_596869.4

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
TTN	ENST00000589042.5	TSL:5 MANE Select	c.18561G>A	p.Ala6187Ala	synonymous	Exon 63 of 363	ENSP00000467141.1
TTN	ENST00000446966.2	TSL:1	c.18561G>A	p.Ala6187Ala	synonymous	Exon 63 of 361	ENSP00000408004.2
TTN	ENST00000436599.2	TSL:1	c.18285G>A	p.Ala6095Ala	synonymous	Exon 61 of 361	ENSP00000405517.2

Frequencies

GnomAD3 genomes

AF:

0.0000592

AC:

AN:

152118

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000193

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00633

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.00000403

AC:

AN:

248186

AF XY:

0.00000743

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:

0.00000892

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000205

AC:

AN:

1461458

Hom.:

Cov.:

AF XY:

0.0000220

AC XY:

AN XY:

727004

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33454

American (AMR)

AF:

0.00

AC:

AN:

44720

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26122

East Asian (EAS)

AF:

0.0000504

AC:

AN:

39692

South Asian (SAS)

AF:

0.00

AC:

AN:

86250

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53400

Middle Eastern (MID)

AF:

0.00243

AC:

AN:

5760

European-Non Finnish (NFE)

AF:

0.00000900

AC:

AN:

1111700

Other (OTH)

AF:

0.0000663

AC:

AN:

60360

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.473

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Exome Hom

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:

0.0000591

AC:

AN:

152236

Hom.:

Cov.:

AF XY:

0.0000537

AC XY:

AN XY:

74434

show subpopulations

African (AFR)

AF:

0.0000241

AC:

AN:

41546

American (AMR)

AF:

0.000131

AC:

AN:

15282

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.000193

AC:

AN:

5174

South Asian (SAS)

AF:

0.000207

AC:

AN:

4824

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10610

Middle Eastern (MID)

AF:

0.00680

AC:

AN:

294

European-Non Finnish (NFE)

AF:

0.0000294

AC:

AN:

68006

Other (OTH)

AF:

0.00

AC:

AN:

2116

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.497

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:

0.0000371

Hom.:

Bravo

AF:

0.0000453

EpiCase

AF:

0.0000546

EpiControl

AF:

0.00

ClinVar

ClinVar submissions as Germline

Significance:Conflicting classifications of pathogenicity

Revision:criteria provided, conflicting classifications

View on ClinVar

Pathogenic

VUS

Benign

Condition

not provided (4)

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

Cardiomyopathy (1)

not specified (1)

TTN-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.42

CADD

Benign

0.11

(source)

DANN

Benign

0.74

PhyloP100

-0.56

Mutation Taster

=81/19

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

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over