chr2-178601562-C-T

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_001267550.2(TTN):c.55435G>A(p.Val18479Ile) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.000041 in 1,608,652 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign outcome for this variant. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000038 ( 1 hom. )

Consequence

TTN
NM_001267550.2 missense, splice_region

Scores

Clinical Significance

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

Conservation

PhyloP100: 3.90

Publications

3 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 -5 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.009603083).

BP6

Variant 2-178601562-C-T is Benign according to our data. Variant chr2-178601562-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 413072.

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.55435G>A	p.Val18479Ile	missense splice_region	Exon 287 of 363	NP_001254479.2
TTN	NM_001256850.1		c.50512G>A	p.Val16838Ile	missense splice_region	Exon 237 of 313	NP_001243779.1
TTN	NM_133378.4		c.47731G>A	p.Val15911Ile	missense splice_region	Exon 236 of 312	NP_596869.4

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
TTN	ENST00000589042.5	TSL:5 MANE Select	c.55435G>A	p.Val18479Ile	missense splice_region	Exon 287 of 363	ENSP00000467141.1
TTN	ENST00000446966.2	TSL:1	c.55279G>A	p.Val18427Ile	missense splice_region	Exon 285 of 361	ENSP00000408004.2
TTN	ENST00000436599.2	TSL:1	c.55159G>A	p.Val18387Ile	missense splice_region	Exon 285 of 361	ENSP00000405517.2

Frequencies

GnomAD3 genomes

AF:

0.0000658

AC:

AN:

152050

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00194

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

GnomAD2 exomes

AF:

0.000192

AC:

AN:

244830

AF XY:

0.000173

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00257

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000384

AC:

AN:

1456484

Hom.:

Cov.:

AF XY:

0.0000345

AC XY:

AN XY:

724172

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33188

American (AMR)

AF:

0.0000226

AC:

AN:

44244

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

25864

East Asian (EAS)

AF:

0.00134

AC:

AN:

39594

South Asian (SAS)

AF:

0.0000117

AC:

AN:

85444

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53232

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5730

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1109078

Other (OTH)

AF:

0.0000166

AC:

AN:

60110

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.511

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:

0.0000657

AC:

AN:

152168

Hom.:

Cov.:

AF XY:

0.0000941

AC XY:

AN XY:

74388

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41556

American (AMR)

AF:

0.00

AC:

AN:

15274

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00195

AC:

AN:

5138

South Asian (SAS)

AF:

0.00

AC:

AN:

4830

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10620

Middle Eastern (MID)

AF:

0.00

AC:

AN:

294

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

67960

Other (OTH)

AF:

0.00

AC:

AN:

2114

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.550

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:

0.000173

Hom.:

Bravo

AF:

0.000113

ExAC

AF:

0.000207

AC:

ClinVar

ClinVar submissions as Germline

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)

Dilated cardiomyopathy 1G;C1861065:Hypertrophic cardiomyopathy 9 (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.091

BayesDel_addAF

Benign

-0.52

BayesDel_noAF

Benign

-0.52

CADD

Benign

(source)

DANN

Benign

0.94

Eigen

Uncertain

0.20

Eigen_PC

Uncertain

0.35

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.84

M_CAP

Benign

0.043

MetaRNN

Benign

0.0096

MetaSVM

Benign

-0.84

MutationAssessor

Benign

1.6

PhyloP100

3.9

PrimateAI

Benign

0.44

PROVEAN

Benign

-0.66

REVEL

Benign

0.12

Sift

Benign

0.30

Polyphen

0.088

Vest4

0.29

MutPred

0.26

Gain of ubiquitination at K16843 (P = 0.0831)

MVP

0.31

MPC

0.079

ClinPred

0.024

GERP RS

5.7

Mutation Taster

=63/37

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