chr2-178618216-T-G

Position:

chr2-178618216-T-G

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 1P and 2B. PP2BP4_Moderate

The NM_001267550.2(TTN):c.47242A>C(p.Asn15748His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000155 in 1,612,620 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 0.000086 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 2.66

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:):

TTN-AS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -1 ACMG points.

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), TTN. . Gene score misZ -1.1021 (greater than the threshold 3.09). Trascript score misZ 6.9794 (greater than threshold 3.09). GenCC has associacion of gene with dilated cardiomyopathy, tibial muscular dystrophy, early-onset myopathy with fatal cardiomyopathy, autosomal recessive centronuclear myopathy, hypertrophic cardiomyopathy, hypertrophic cardiomyopathy 9, TTN-related myopathy, dilated cardiomyopathy 1G, arrhythmogenic right ventricular cardiomyopathy, myopathy, myofibrillar, 9, with early respiratory failure, familial isolated dilated cardiomyopathy, childhood-onset progressive contractures-limb-girdle weakness-muscle dystrophy syndrome, autosomal recessive limb-girdle muscular dystrophy type 2J.

BP4

Computational evidence support a benign effect (MetaRNN=0.11505985).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TTN	NM_001267550.2 linkuse as main transcript	c.47242A>C	p.Asn15748His	missense_variant	252/363	ENST00000589042.5	NP_001254479.2	A0A0A0MTS7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TTN	ENST00000589042.5 linkuse as main transcript	c.47242A>C	p.Asn15748His	missense_variant	252/363	5	NM_001267550.2	ENSP00000467141.1		A0A0A0MTS7

Frequencies

GnomAD3 genomes

AF:

0.0000856

AC:

AN:

151932

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000290

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:

0.00

Gnomad OTH

AF:

0.000479

GnomAD3 exomes

AF:

0.0000161

AC:

AN:

248010

Hom.:

AF XY:

0.0000149

AC XY:

AN XY:

134546

show subpopulations

Gnomad AFR exome

AF:

0.000259

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000822

AC:

AN:

1460688

Hom.:

Cov.:

AF XY:

0.00000550

AC XY:

AN XY:

726638

show subpopulations

Gnomad4 AFR exome

AF:

0.000269

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

9.00e-7

Gnomad4 OTH exome

AF:

0.0000332

GnomAD4 genome

AF:

0.0000856

AC:

AN:

151932

Hom.:

Cov.:

AF XY:

0.0000943

AC XY:

AN XY:

74204

show subpopulations

Gnomad4 AFR

AF:

0.000290

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000479

Alfa

AF:

0.0000565

Hom.:

Bravo

AF:

0.000102

ESP6500AA

AF:

0.000788

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000248

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not specified

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	May 03, 2013	Variant classified as Uncertain Significance - Favor Benign. The Asn13180His var iant in TTN has not been reported in individuals with cardiomyopathy, but has be en identified in 3/3806 African American chromosomes by the NHLBI Exome Sequenci ng Project (http://evs.gs.washington.edu/EVS/). Asparagine (Asn) at position 13 180 is poorly conserved in evolution, including in mammals, suggesting that a ch ange at this position would be tolerated. Other computational analyses (biochemi cal amino acid properties, AlignGVGD, PolyPhen2, and SIFT) also suggest that thi s variant may not impact the protein, though this information is not predictive enough to rule out pathogenicity. The presence of the variant in the general pop ulation and poor evolutionary conservation suggest that the Asn13180His variant may be benign; however, additional studies are needed to fully assess its clinic al significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Nov 15, 2021	- -

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Mar 12, 2013	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Mar 07, 2022	- -

Cardiovascular phenotype

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 12, 2020

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.064

BayesDel_addAF

Benign

-0.39

BayesDel_noAF

Benign

-0.50

CADD

Benign

DANN

Benign

0.91

Eigen

Benign

0.046

Eigen_PC

Benign

0.22

FATHMM_MKL

Uncertain

0.96

LIST_S2

Benign

0.85

T;T;T;.;T;T;T

M_CAP

Benign

0.022

MetaRNN

Benign

0.12

T;T;T;T;T;T;T

MetaSVM

Benign

-0.77

MutationAssessor

Benign

1.4

.;.;.;L;.;.;L

MutationTaster

Benign

0.88

N;N;N;N;N;N

PrimateAI

Benign

0.31

PROVEAN

Uncertain

-2.6

D;N;.;.;N;N;.

REVEL

Benign

0.13

Sift

Benign

0.10

T;T;.;.;T;T;.

Polyphen

0.16

.;.;.;B;.;.;B

Vest4

0.33

MVP

0.29

MPC

0.10

ClinPred

0.057

GERP RS

5.6

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over