2-178792149-C-T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 1P and 5B. PP2BP4_StrongBP6

The NM_001267550.2(TTN):​c.1585G>A​(p.Ala529Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000062 in 1,611,722 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/18 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 0.00011 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000057 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

17

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:5

Conservation

PhyloP100: -1.05
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 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=0.016406327).
BP6
Variant 2-178792149-C-T is Benign according to our data. Variant chr2-178792149-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 178275.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=5, Uncertain_significance=8}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTNNM_001267550.2 linkuse as main transcriptc.1585G>A p.Ala529Thr missense_variant 10/363 ENST00000589042.5 NP_001254479.2
TTNNM_133379.5 linkuse as main transcriptc.1585G>A p.Ala529Thr missense_variant 10/46 ENST00000360870.10 NP_596870.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkuse as main transcriptc.1585G>A p.Ala529Thr missense_variant 10/3635 NM_001267550.2 ENSP00000467141 P1
TTNENST00000360870.10 linkuse as main transcriptc.1585G>A p.Ala529Thr missense_variant 10/465 NM_133379.5 ENSP00000354117 Q8WZ42-6

Frequencies

GnomAD3 genomes
AF:
0.000112
AC:
17
AN:
152082
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000962
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000118
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000521
AC:
13
AN:
249508
Hom.:
0
AF XY:
0.0000593
AC XY:
8
AN XY:
134818
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000164
Gnomad SAS exome
AF:
0.0000332
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000796
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000569
AC:
83
AN:
1459522
Hom.:
0
Cov.:
31
AF XY:
0.0000565
AC XY:
41
AN XY:
725992
show subpopulations
Gnomad4 AFR exome
AF:
0.0000300
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000506
Gnomad4 SAS exome
AF:
0.0000700
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000639
Gnomad4 OTH exome
AF:
0.0000498
GnomAD4 genome
AF:
0.000112
AC:
17
AN:
152200
Hom.:
0
Cov.:
32
AF XY:
0.000134
AC XY:
10
AN XY:
74420
show subpopulations
Gnomad4 AFR
AF:
0.0000722
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000964
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.000118
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000763
Hom.:
0
Bravo
AF:
0.0000416
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.0000659
AC:
8
EpiCase
AF:
0.000109
EpiControl
AF:
0.000178

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:7Benign:5
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3Benign:1
Likely benign, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenAug 01, 2024TTN: BP4 -
Uncertain significance, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Mar 07, 2017- -
Uncertain significance, criteria provided, single submitterclinical testingRevvity Omics, RevvityMar 27, 2023- -
Uncertain significance, criteria provided, single submitterresearchBiesecker Lab/Clinical Genomics Section, National Institutes of HealthJun 24, 2013- -
Autosomal recessive limb-girdle muscular dystrophy type 2J Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 13, 2018This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpDec 01, 2017- -
Dilated cardiomyopathy 1G Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 13, 2018This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Early-onset myopathy with fatal cardiomyopathy Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 13, 2018This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
not specified Benign:1
Likely benign, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineAug 22, 2013Ala529Thr in exon 10 of TTN: This variant is not expected to have clinical signi ficance due to a lack of conservation in mammals and across species. Of note, >1 0 mammals have a threonine (Thr; this variant) at this position despite high nea rby amino acid conservation. In addition, computational analyses (AlignGVGD, Pol yPhen2, SIFT) do not suggest a high likelihood of impact to the protein. This va riant has been identified in 1/4398 African American chromosomes and 1/8592 Euro pean American chromosomes from a broad population by the NHLBI Exome Sequencing Project (http://evs.gs.washington.edu/EVS/; dbSNP rs143030869). -
Myopathy, myofibrillar, 9, with early respiratory failure Benign:1
Likely benign, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 13, 2018This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -
Tibial muscular dystrophy Benign:1
Likely benign, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 13, 2018This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -
Cardiovascular phenotype Benign:1
Likely benign, criteria provided, single submitterclinical testingAmbry GeneticsAug 11, 2019This 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
0.071
BayesDel_addAF
Benign
-0.42
T
BayesDel_noAF
Benign
-0.65
CADD
Benign
0.92
DANN
Benign
0.26
Eigen
Benign
-2.0
Eigen_PC
Benign
-2.1
FATHMM_MKL
Benign
0.0036
N
LIST_S2
Benign
0.57
T;T;T;.;T;T;T;T;T
M_CAP
Benign
0.055
D
MetaRNN
Benign
0.016
T;T;T;T;T;T;T;T;T
MetaSVM
Benign
-0.84
T
MutationTaster
Benign
1.0
N;N;N;N;N;N;N
PrimateAI
Benign
0.29
T
PROVEAN
Benign
-1.5
N;N;.;.;N;N;.;N;N
REVEL
Benign
0.073
Sift
Benign
0.13
T;T;.;.;T;T;.;T;T
Sift4G
Benign
0.12
.;.;.;.;.;.;.;T;.
Polyphen
0.0010, 0.015
.;.;.;B;.;.;B;B;.
Vest4
0.093
MVP
0.014
MPC
0.081
ClinPred
0.030
T
GERP RS
-12

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.

Other links and lift over

dbSNP: rs143030869; hg19: chr2-179656876; COSMIC: COSV60344436; API