2-178777893-G-A

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_001267550.2(TTN):c.4291C>T(p.Arg1431Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000731 in 1,613,836 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 11/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1431Q) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00015 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000065 ( 1 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 2.09

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:

LOC101927055 (HGNC:):

LOC101927055 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.10537022).

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.4291C>T	p.Arg1431Trp	missense	Exon 25 of 363	NP_001254479.2	Q8WZ42-12
TTN	NM_001256850.1		c.4291C>T	p.Arg1431Trp	missense	Exon 25 of 313	NP_001243779.1	Q8WZ42-1
TTN	NM_133378.4		c.4291C>T	p.Arg1431Trp	missense	Exon 25 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.4291C>T	p.Arg1431Trp	missense	Exon 25 of 363	ENSP00000467141.1	Q8WZ42-12
TTN	ENST00000446966.2	TSL:1	c.4291C>T	p.Arg1431Trp	missense	Exon 25 of 361	ENSP00000408004.2	A0A1B0GXE3
TTN	ENST00000436599.2	TSL:1	c.4015C>T	p.Arg1339Trp	missense	Exon 23 of 361	ENSP00000405517.2	A0A0C4DG59

Frequencies

GnomAD3 genomes

AF:

0.000151

AC:

AN:

152116

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000507

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000414

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.000120

AC:

AN:

250728

AF XY:

0.000133

show subpopulations

Gnomad AFR exome

AF:

0.000492

Gnomad AMR exome

AF:

0.0000290

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000545

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000883

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000650

AC:

AN:

1461602

Hom.:

Cov.:

AF XY:

0.0000756

AC XY:

AN XY:

727110

show subpopulations

African (AFR)

AF:

0.000717

AC:

AN:

33464

American (AMR)

AF:

0.00

AC:

AN:

44704

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26128

East Asian (EAS)

AF:

0.0000252

AC:

AN:

39664

South Asian (SAS)

AF:

0.000638

AC:

AN:

86250

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53412

Middle Eastern (MID)

AF:

0.000173

AC:

AN:

5764

European-Non Finnish (NFE)

AF:

0.00000809

AC:

AN:

1111836

Other (OTH)

AF:

0.0000828

AC:

AN:

60380

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.490

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:

0.000151

AC:

AN:

152234

Hom.:

Cov.:

AF XY:

0.000188

AC XY:

AN XY:

74438

show subpopulations

African (AFR)

AF:

0.000505

AC:

AN:

41552

American (AMR)

AF:

0.00

AC:

AN:

15280

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5182

South Asian (SAS)

AF:

0.000415

AC:

AN:

4822

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10602

Middle Eastern (MID)

AF:

0.00

AC:

AN:

294

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68006

Other (OTH)

AF:

0.00

AC:

AN:

2114

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.495

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:

0.0000764

Hom.:

Bravo

AF:

0.000151

ESP6500AA

AF:

0.000908

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.000165

AC:

ClinVar

ClinVar submissions

Significance:Conflicting classifications of pathogenicity

Revision:criteria provided, conflicting classifications

View on ClinVar

Pathogenic

VUS

Benign

Condition

not provided (3)

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

Cardiovascular phenotype (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.87

BayesDel_addAF

Benign

-0.25

BayesDel_noAF

Benign

-0.23

CADD

Benign

(source)

DANN

Benign

0.96

Eigen

Benign

0.13

Eigen_PC

Benign

0.15

FATHMM_MKL

Uncertain

0.87

LIST_S2

Uncertain

0.94

M_CAP

Benign

0.051

MetaRNN

Benign

0.11

MetaSVM

Benign

-0.59

PhyloP100

2.1

PrimateAI

Pathogenic

0.82

PROVEAN

Uncertain

-3.5

REVEL

Uncertain

0.32

Sift

Uncertain

0.0060

Sift4G

Pathogenic

0.0010

Polyphen

0.99

Vest4

0.30

MVP

0.35

MPC

0.18

ClinPred

0.067

GERP RS

4.1

Mutation Taster

=97/3

polymorphism

(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