2-178609974-G-A

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 0P and 1B. BP4

The NM_001267550.2(TTN):c.51449C>T(p.Pro17150Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000373 in 1,610,730 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 9.94

Publications

2 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 -1 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.3805957).

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.51449C>T	p.Pro17150Leu	missense	Exon 272 of 363	NP_001254479.2
TTN	NM_001256850.1		c.46526C>T	p.Pro15509Leu	missense	Exon 222 of 313	NP_001243779.1
TTN	NM_133378.4		c.43745C>T	p.Pro14582Leu	missense	Exon 221 of 312	NP_596869.4

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
TTN	ENST00000589042.5	TSL:5 MANE Select	c.51449C>T	p.Pro17150Leu	missense	Exon 272 of 363	ENSP00000467141.1
TTN	ENST00000446966.2	TSL:1	c.51293C>T	p.Pro17098Leu	missense	Exon 270 of 361	ENSP00000408004.2
TTN	ENST00000436599.2	TSL:1	c.51173C>T	p.Pro17058Leu	missense	Exon 270 of 361	ENSP00000405517.2

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

151896

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000242

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:

0.00

GnomAD2 exomes

AF:

0.00000406

AC:

AN:

246534

AF XY:

0.00000748

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:

0.00000895

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000343

AC:

AN:

1458834

Hom.:

Cov.:

AF XY:

0.00000551

AC XY:

AN XY:

725702

show subpopulations

African (AFR)

AF:

0.0000603

AC:

AN:

33184

American (AMR)

AF:

0.00

AC:

AN:

44278

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26052

East Asian (EAS)

AF:

0.00

AC:

AN:

39562

South Asian (SAS)

AF:

0.00

AC:

AN:

85878

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53184

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5746

European-Non Finnish (NFE)

AF:

0.00000180

AC:

AN:

1110740

Other (OTH)

AF:

0.0000166

AC:

AN:

60210

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.455

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:

0.00000658

AC:

AN:

151896

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74162

show subpopulations

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR)

AF:

0.0000242

AC:

AN:

41404

American (AMR)

AF:

0.00

AC:

AN:

15232

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3468

East Asian (EAS)

AF:

0.00

AC:

AN:

5130

South Asian (SAS)

AF:

0.00

AC:

AN:

4808

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10614

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

67924

Other (OTH)

AF:

0.00

AC:

AN:

2088

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.375

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:

0.00

Hom.:

Bravo

AF:

0.00000756

ExAC

AF:

0.00000828

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

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

Uncertain:1

May 11, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1838244:Tibial muscular dystrophy;C1858763:Dilated cardiomyopathy 1G;C1861065:Hypertrophic cardiomyopathy 9;C1863599:Myopathy, myofibrillar, 9, with early respiratory failure;C2673677:Early-onset myopathy with fatal cardiomyopathy

Uncertain:1

Jul 23, 2021

Fulgent Genetics, Fulgent Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.60

BayesDel_addAF

Uncertain

0.081

BayesDel_noAF

Benign

-0.12

CADD

Benign

(source)

DANN

Benign

0.96

Eigen

Pathogenic

1.1

Eigen_PC

Pathogenic

1.0

FATHMM_MKL

Pathogenic

1.0

LIST_S2

Uncertain

0.96

M_CAP

Benign

0.018

MetaRNN

Benign

0.38

MetaSVM

Uncertain

0.26

MutationAssessor

Pathogenic

4.1

PhyloP100

9.9

PrimateAI

Uncertain

0.56

PROVEAN

Pathogenic

-7.0

REVEL

Uncertain

0.50

Sift

Uncertain

0.0040

Polyphen

1.0

Vest4

0.35

MutPred

0.47

Loss of disorder (P = 0.0238)

MVP

0.67

MPC

0.47

ClinPred

0.94

GERP RS

5.7

Mutation Taster

=52/48

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

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over