rs149059189

Variant summary

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

The NM_001267550.2(TTN):​c.41488G>A​(p.Val13830Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000781 in 1,613,250 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 0.00040 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000044 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

17

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:7

Conservation

PhyloP100: 0.0690
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=0.011718988).
BP6
Variant 2-178636083-C-T is Benign according to our data. Variant chr2-178636083-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 202620.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=5, Uncertain_significance=2, Benign=1}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTNNM_001267550.2 linkuse as main transcriptc.41488G>A p.Val13830Ile missense_variant 226/363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkuse as main transcriptc.41488G>A p.Val13830Ile missense_variant 226/3635 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000401
AC:
61
AN:
152008
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00126
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000194
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000736
Gnomad OTH
AF:
0.000479
GnomAD3 exomes
AF:
0.000105
AC:
26
AN:
248378
Hom.:
0
AF XY:
0.0000891
AC XY:
12
AN XY:
134738
show subpopulations
Gnomad AFR exome
AF:
0.00123
Gnomad AMR exome
AF:
0.000116
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:
0.0000267
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000445
AC:
65
AN:
1461124
Hom.:
0
Cov.:
32
AF XY:
0.0000358
AC XY:
26
AN XY:
726842
show subpopulations
Gnomad4 AFR exome
AF:
0.00129
Gnomad4 AMR exome
AF:
0.0000671
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000108
Gnomad4 OTH exome
AF:
0.0000994
GnomAD4 genome
AF:
0.000401
AC:
61
AN:
152126
Hom.:
0
Cov.:
32
AF XY:
0.000417
AC XY:
31
AN XY:
74368
show subpopulations
Gnomad4 AFR
AF:
0.00125
Gnomad4 AMR
AF:
0.000131
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000194
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000736
Gnomad4 OTH
AF:
0.000474
Alfa
AF:
0.000644
Hom.:
0
Bravo
AF:
0.000416
ESP6500AA
AF:
0.00123
AC:
5
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000140
AC:
17
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:7
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1Benign:3
Uncertain significance, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Jun 11, 2015- -
Likely benign, criteria provided, single submitterclinical testingGeneDxJun 02, 2020- -
Likely benign, criteria provided, single submitterclinical testingAthena DiagnosticsOct 30, 2018- -
Likely benign, criteria provided, single submitterclinical testingRevvity Omics, RevvityApr 04, 2023- -
Cardiovascular phenotype Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsSep 25, 2013The p.V11262I variant (also known as c.33784G>A) is located in coding exon 174 of the TTN gene. This alteration results from a G to A substitution at nucleotide position 33784. The valine at codon 11262 is replaced by isoleucine, an amino acid with highly similar properties. ​ ​This variant was previously reported in the SNPDatabase as rs149059189. Based on data from the NHLBI Exome Sequencing Project (ESP), the A-allele has an overall frequency of approximately 0.04% (5/12,442), having been observed in 0.12% (5/4078) of African American alleles, and not observed in 8364 European American alleles studied. Based on data from the 1000 Genomes Project, the A-allele has an overall frequency of approximately 0.05% (1/2184). The highest observed frequency was 0.52% (1/194) Luhya chromosomes studied. This amino acid position is poorly conserved in available vertebrate species. This variant is predicted to be benign by PolyPhen in silico analyses. Since supporting evidence is limited at this time, the clinical significance of p.V11262I remains unclear. -
not specified Benign:1
Likely benign, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpNov 20, 2023Variant summary: TTN c.33784G>A (p.Val11262Ile) results in a conservative amino acid change located in the I-band region 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 0.0001 in 248378 control chromosomes, predominantly at a frequency of 0.0012 within the African or African-American subpopulation in the gnomAD database. The observed variant frequency within African or African-American control individuals in the gnomAD database is approximately 3-fold of 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 African or African-American origin. To our knowledge, no occurrence of c.33784G>A in individuals affected with Dilated Cardiomyopathy and no experimental evidence demonstrating its impact on protein function have been reported. Six submitters have reported clinical-significance assessments for this variant to ClinVar after 2014. Multiple submitters reported the variant with conflicting assessments (benign, n = 1; likely benign, n = 3; uncertain significance, n = 2). Based on the evidence outlined above, the variant was classified as likely benign. -
TTN-related disorder Benign:1
Likely benign, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesMar 13, 2024This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Benign:1
Likely benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 31, 2024- -
Cardiomyopathy Benign:1
Benign, criteria provided, single submitterclinical testingCHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern OntarioMay 08, 2020- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.070
BayesDel_addAF
Benign
-0.62
T
BayesDel_noAF
Benign
-0.67
CADD
Benign
2.9
DANN
Benign
0.80
Eigen
Benign
-1.1
Eigen_PC
Benign
-1.1
FATHMM_MKL
Benign
0.037
N
LIST_S2
Benign
0.68
T;T;T;.;T;T;T
M_CAP
Benign
0.010
T
MetaRNN
Benign
0.012
T;T;T;T;T;T;T
MetaSVM
Benign
-0.96
T
MutationAssessor
Benign
-0.15
.;.;.;N;.;.;N
PrimateAI
Benign
0.38
T
PROVEAN
Benign
-0.48
N;N;.;.;N;N;.
REVEL
Benign
0.030
Sift
Benign
0.38
T;T;.;.;T;T;.
Polyphen
0.019
.;.;.;B;.;.;B
Vest4
0.11
MVP
0.072
MPC
0.070
ClinPred
0.0028
T
GERP RS
-0.079

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: rs149059189; hg19: chr2-179500810; COSMIC: COSV59888669; COSMIC: COSV59888669; API