rs184740744

Variant summary

Our verdict is Benign. Variant got -19 ACMG points: 1P and 20B. PP2BP4_StrongBP6_Very_StrongBS1BS2

The NM_001267550.2(TTN):​c.14765G>A​(p.Ser4922Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00127 in 1,613,802 control chromosomes in the GnomAD database, including 59 homozygotes. In-silico tool predicts a benign outcome for this variant. 13/17 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0019 ( 6 hom., cov: 33)
Exomes 𝑓: 0.0012 ( 53 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

15

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:21

Conservation

PhyloP100: -0.0620
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 Benign. Variant got -19 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=0.0028292537).
BP6
Variant 2-178735681-C-T is Benign according to our data. Variant chr2-178735681-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 46592.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-178735681-C-T is described in Lovd as [Likely_benign].
BS1
Variant frequency is greater than expected in population amr. gnomad4 allele frequency = 0.00192 (292/152284) while in subpopulation AMR AF= 0.0176 (269/15282). AF 95% confidence interval is 0.0159. There are 6 homozygotes in gnomad4. There are 154 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
BS2
High Homozygotes in GnomAd4 at 6 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTNNM_001267550.2 linkuse as main transcriptc.14765G>A p.Ser4922Asn missense_variant 50/363 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.14765G>A p.Ser4922Asn missense_variant 50/3635 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.00190
AC:
289
AN:
152166
Hom.:
6
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000458
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0174
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00143
GnomAD3 exomes
AF:
0.00587
AC:
1460
AN:
248644
Hom.:
41
AF XY:
0.00414
AC XY:
558
AN XY:
134910
show subpopulations
Gnomad AFR exome
AF:
0.000452
Gnomad AMR exome
AF:
0.0414
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000981
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000266
Gnomad OTH exome
AF:
0.00333
GnomAD4 exome
AF:
0.00121
AC:
1764
AN:
1461518
Hom.:
53
Cov.:
29
AF XY:
0.000970
AC XY:
705
AN XY:
727032
show subpopulations
Gnomad4 AFR exome
AF:
0.000508
Gnomad4 AMR exome
AF:
0.0376
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000696
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000360
Gnomad4 OTH exome
AF:
0.000895
GnomAD4 genome
AF:
0.00192
AC:
292
AN:
152284
Hom.:
6
Cov.:
33
AF XY:
0.00207
AC XY:
154
AN XY:
74464
show subpopulations
Gnomad4 AFR
AF:
0.000457
Gnomad4 AMR
AF:
0.0176
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000207
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00142
Alfa
AF:
0.000403
Hom.:
1
Bravo
AF:
0.00383
ESP6500AA
AF:
0.000537
AC:
2
ESP6500EA
AF:
0.000122
AC:
1
ExAC
AF:
0.00421
AC:
508
Asia WGS
AF:
0.00115
AC:
4
AN:
3476
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:21
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:5
Benign, criteria provided, single submitterclinical testingGeneDxFeb 18, 2016This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Benign, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineDec 23, 2014p.Ser3678Asn in exon 47 of TTN: This variant is not expected to have clinical si gnificance because it has been identified in 4.3% (495/11530) of Latino chromoso mes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs184740744). In addition, multiple mammals carry an asparagine (Asn) at t his position, despite high amino acid conservation nearby, supporting that this change would be tolerated. -
Benign, criteria provided, single submitterclinical testingAthena DiagnosticsSep 27, 2016- -
Benign, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpJan 09, 2023Variant summary: TTN c.11033G>A (p.Ser3678Asn) results in a conservative amino acid change in the encoded protein sequence. Two of two in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.0059 in 248644 control chromosomes in the gnomAD database, including 41 homozygotes. The observed variant frequency is approximately 9 fold of the estimated maximal expected allele frequency for a pathogenic variant in TTN causing Cardiomyopathy phenotype (0.00063), strongly suggesting that the variant is benign. Eleven clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as benign/likely benign. Based on the evidence outlined above, the variant was classified as benign. -
Benign, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Aug 17, 2015- -
not provided Benign:3
Likely benign, criteria provided, single submitterclinical testingGenetic Services Laboratory, University of ChicagoFeb 10, 2015- -
Benign, criteria provided, single submitterclinical testingARUP Laboratories, Molecular Genetics and Genomics, ARUP LaboratoriesNov 22, 2023- -
Likely benign, criteria provided, single submitternot providedBreakthrough Genomics, Breakthrough Genomics-- -
Autosomal recessive limb-girdle muscular dystrophy type 2J Benign:2
Benign, criteria provided, single submitterclinical testingGenome-Nilou LabSep 10, 2021- -
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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Cardiomyopathy Benign:2
Benign, criteria provided, single submitterclinical testingCHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern OntarioJan 31, 2018- -
Benign, criteria provided, single submitterclinical testingCenter for Advanced Laboratory Medicine, UC San Diego Health, University of California San DiegoMay 14, 2019- -
Early-onset myopathy with fatal cardiomyopathy Benign:2
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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Benign, criteria provided, single submitterclinical testingGenome-Nilou LabSep 10, 2021- -
Tibial muscular dystrophy Benign:2
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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Benign, criteria provided, single submitterclinical testingGenome-Nilou LabSep 10, 2021- -
Myopathy, myofibrillar, 9, with early respiratory failure Benign:2
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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Benign, criteria provided, single submitterclinical testingGenome-Nilou LabSep 10, 2021- -
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Benign:1
Benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 31, 2024- -
Dilated cardiomyopathy 1G 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
Benign, criteria provided, single submitterclinical testingAmbry GeneticsApr 11, 2013This alteration is classified as benign based on a combination of the following: 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
0.058
BayesDel_addAF
Benign
-0.66
T
BayesDel_noAF
Benign
-0.69
CADD
Benign
4.3
DANN
Benign
0.69
Eigen
Benign
-1.0
Eigen_PC
Benign
-1.1
FATHMM_MKL
Benign
0.044
N
LIST_S2
Benign
0.41
T;T;.;T
MetaRNN
Benign
0.0028
T;T;T;T
MetaSVM
Benign
-1.0
T
PrimateAI
Benign
0.30
T
PROVEAN
Benign
-0.86
N;.;.;.
REVEL
Benign
0.12
Sift
Benign
0.22
T;.;.;.
Polyphen
0.0
.;.;B;B
Vest4
0.039
MVP
0.030
MPC
0.078
ClinPred
0.0019
T
GERP RS
-6.1

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: rs184740744; hg19: chr2-179600408; COSMIC: COSV104642441; COSMIC: COSV104642441; API