rs148140756

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_001267550.2(TTN):​c.39689C>T​(p.Ala13230Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000981 in 1,606,584 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. A13230A) has been classified as Benign.

Frequency

Genomes: 𝑓 0.00057 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0010 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

17

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:10

Conservation

PhyloP100: -0.246
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-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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.005412787).
BP6
Variant 2-178650771-G-A is Benign according to our data. Variant chr2-178650771-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 166080.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=6, Benign=4, Uncertain_significance=4}. Variant chr2-178650771-G-A is described in Lovd as [Likely_benign].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.39689C>T p.Ala13230Val missense_variant Exon 209 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.39689C>T p.Ala13230Val missense_variant Exon 209 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000572
AC:
87
AN:
152162
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000314
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.00101
Gnomad OTH
AF:
0.000478
GnomAD3 exomes
AF:
0.000503
AC:
120
AN:
238506
Hom.:
0
AF XY:
0.000403
AC XY:
52
AN XY:
128956
show subpopulations
Gnomad AFR exome
AF:
0.000206
Gnomad AMR exome
AF:
0.00146
Gnomad ASJ exome
AF:
0.000102
Gnomad EAS exome
AF:
0.0000578
Gnomad SAS exome
AF:
0.0000348
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000575
Gnomad OTH exome
AF:
0.000514
GnomAD4 exome
AF:
0.00102
AC:
1489
AN:
1454304
Hom.:
0
Cov.:
31
AF XY:
0.000958
AC XY:
692
AN XY:
722594
show subpopulations
Gnomad4 AFR exome
AF:
0.000240
Gnomad4 AMR exome
AF:
0.00125
Gnomad4 ASJ exome
AF:
0.0000386
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000355
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00117
Gnomad4 OTH exome
AF:
0.00200
GnomAD4 genome
AF:
0.000571
AC:
87
AN:
152280
Hom.:
0
Cov.:
32
AF XY:
0.000376
AC XY:
28
AN XY:
74460
show subpopulations
Gnomad4 AFR
AF:
0.000313
Gnomad4 AMR
AF:
0.000131
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000414
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00101
Gnomad4 OTH
AF:
0.000473
Alfa
AF:
0.000667
Hom.:
1
Bravo
AF:
0.000623
TwinsUK
AF:
0.000809
AC:
3
ALSPAC
AF:
0.00130
AC:
5
ESP6500AA
AF:
0.000264
AC:
1
ESP6500EA
AF:
0.00208
AC:
17
ExAC
AF:
0.000489
AC:
59

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:10
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1Benign:4
Oct 06, 2020
GeneDx
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant is associated with the following publications: (PMID: 23396983) -

Jun 07, 2017
Eurofins Ntd Llc (ga)
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Apr 16, 2019
Athena Diagnostics
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jun 24, 2013
Biesecker Lab/Clinical Genomics Section, National Institutes of Health
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: research

- -

Mar 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

TTN: PM2:Supporting, BP1, BP4 -

not specified Benign:2
Apr 17, 2014
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

p.Ala10796Val in exon 163 of TTN: This variant is not expected to have clinical significance due to a lack of conservation across species, including mammals. Of note, >40 species including primates, rats and mice have a valine (Val) at this position despite high nearby amino acid conservation. The Ala10796Val variant a lso been identified in 0.21% (17/8192) of European American chromosomes by the N HLBI Exome Sequencing Project (http://evs.gs.washington.edu/EVS/; dbSNP rs148140 756). -

Mar 25, 2021
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: TTN c.32387C>T (p.Ala10796Val) results in a non-conservative amino acid change located in the I-band region (cardiodb.org) of the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.0005 in 238506 control chromosomes, predominantly at a frequency of 0.0015 within the Latino subpopulation in the gnomAD database. The observed variant frequency within Latino control individuals in the gnomAD database is approximately 3.8- fold the estimated maximal expected allele frequency for a pathogenic variant in TTN causing Dilated Cardiomyopathy phenotype (0.00039), strongly suggesting that the variant is a benign polymorphism found primarily in populations of Latino origin. c.32387C>T has been reported in the literature in at least one individual affected with Cardiomyopathy without strong evidence for causality (e.g. Lopes_2013). This report does not provide unequivocal conclusions about association of the variant with Dilated Cardiomyopathy. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Six other clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation, citing the variant as benign/likely benign (n=4) and uncertain significance (n=2). Based on the evidence outlined above, the variant was classified as benign. -

Autosomal recessive limb-girdle muscular dystrophy type 2J Uncertain:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This 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. -

Dilated cardiomyopathy 1G Uncertain:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This 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
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This 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 Benign:1
Jan 28, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Cardiomyopathy Benign:1
Jul 08, 2022
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Myopathy, myofibrillar, 9, with early respiratory failure Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This 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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Tibial muscular dystrophy Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This 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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.058
BayesDel_addAF
Benign
-0.55
T
BayesDel_noAF
Benign
-0.59
CADD
Benign
0.28
DANN
Benign
0.73
Eigen
Benign
-1.4
Eigen_PC
Benign
-1.4
FATHMM_MKL
Benign
0.016
N
LIST_S2
Benign
0.46
T;T;.;T;T
M_CAP
Benign
0.011
T
MetaRNN
Benign
0.0054
T;T;T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
-1.6
.;.;N;N;.
PrimateAI
Benign
0.28
T
PROVEAN
Benign
0.34
N;.;.;.;N
REVEL
Benign
0.087
Sift
Benign
0.26
T;.;.;.;T
Polyphen
0.0
.;.;B;B;.
Vest4
0.078
MVP
0.048
MPC
0.083
ClinPred
0.0024
T
GERP RS
-3.3

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: rs148140756; hg19: chr2-179515498; API