2-178718467-T-G

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.24639A>C(p.Gln8213His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000106 in 1,613,608 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000085 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00011 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: -0.337

Publications

1 publications found

Variant links:

COSMIC-nc: COSV104641725

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 -2 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.17684689).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TTN	NM_001267550.2 link	c.24639A>C	p.Gln8213His	missense_variant	Exon 85 of 363	ENST00000589042.5	NP_001254479.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TTN	ENST00000589042.5 link	c.24639A>C	p.Gln8213His	missense_variant	Exon 85 of 363	5	NM_001267550.2	ENSP00000467141.1

Frequencies

GnomAD3 genomes

AF:

0.0000855

AC:

AN:

152118

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:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000191

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000282

AC:

AN:

248386

AF XY:

0.0000297

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000290

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000535

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000108

AC:

158

AN:

1461490

Hom.:

Cov.:

AF XY:

0.000100

AC XY:

AN XY:

727022

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33462

American (AMR)

AF:

0.0000224

AC:

AN:

44710

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26124

East Asian (EAS)

AF:

0.00

AC:

AN:

39682

South Asian (SAS)

AF:

0.00

AC:

AN:

86258

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53394

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5766

European-Non Finnish (NFE)

AF:

0.000127

AC:

141

AN:

1111736

Other (OTH)

AF:

0.000265

AC:

AN:

60358

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.458

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:

0.0000855

AC:

AN:

152118

Hom.:

Cov.:

AF XY:

0.0000942

AC XY:

AN XY:

74302

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41444

American (AMR)

AF:

0.00

AC:

AN:

15258

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5172

South Asian (SAS)

AF:

0.00

AC:

AN:

4830

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10618

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.000191

AC:

AN:

68004

Other (OTH)

AF:

0.00

AC:

AN:

2092

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.483

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:

0.0000966

Hom.:

Bravo

AF:

0.000113

ExAC

AF:

0.0000414

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.000178

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:2Benign:1

Jan 01, 2022

CeGaT Center for Human Genetics Tuebingen

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Feb 07, 2020

GeneDx

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Aug 02, 2023

Revvity Omics, Revvity

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

not specified

Uncertain:1

Sep 01, 2012

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Variant classified as Uncertain Significance - Favor Benign. The Gln6969His vari ant in TTN has not been reported in the literature nor previously identified by our laboratory. Glutamine (Gln) at position 6969 is not well conserved in evolut ion and 2 mammals (pika and shrew) carry a histidine (His; this variant), suppor ting that this change may be tolerated. Other computational analyses (biochemica l amino acid properties, AlignGVGD, and PolyPhen2) also suggest that this varian t may not impact the protein, though this information is not predictive enough t o rule out pathogenicity. In summary, additional information is needed to fully assess the clinical significance of the Gln6969His variant. -

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

Uncertain:1

Oct 10, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.20

BayesDel_addAF

Benign

-0.21

BayesDel_noAF

Benign

-0.38

CADD

Benign

4.1

(source)

DANN

Benign

0.56

Eigen

Benign

-0.86

Eigen_PC

Benign

-0.83

FATHMM_MKL

Benign

0.26

LIST_S2

Benign

0.41

T;T;.;T

M_CAP

Benign

0.014

MetaRNN

Benign

0.18

T;T;T;T

MetaSVM

Benign

-0.95

PhyloP100

-0.34

PrimateAI

Benign

0.35

PROVEAN

Uncertain

-2.8

D;.;.;.

REVEL

Benign

0.080

Sift

Benign

0.053

T;.;.;.

Polyphen

0.0020

.;.;B;B

Vest4

0.25

MutPred

0.39

.;.;Gain of catalytic residue at E7898 (P = 0.1111);Gain of catalytic residue at E7898 (P = 0.1111);

MVP

0.13

MPC

0.079

ClinPred

0.030

GERP RS

-0.23

Mutation Taster

=88/12

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

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over