rs77968867

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_001267550.2(TTN):​c.92537T>C​(p.Val30846Ala) variant causes a missense change. The variant allele was found at a frequency of 0.000459 in 1,613,776 control chromosomes in the GnomAD database, including 3 homozygotes. In-silico tool predicts a benign outcome for this variant. 13/19 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: š‘“ 0.0025 ( 0 hom., cov: 33)
Exomes š‘“: 0.00025 ( 3 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

3
14

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:19

Conservation

PhyloP100: 5.29
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 Benign. Variant got -13 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.0078112483).
BP6
Variant 2-178549089-A-G is Benign according to our data. Variant chr2-178549089-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 47525.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=5, Benign=10, Uncertain_significance=1}. Variant chr2-178549089-A-G is described in Lovd as [Benign]. Variant chr2-178549089-A-G is described in Lovd as [Likely_benign].
BS1
Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00246 (375/152180) while in subpopulation AFR AF= 0.00876 (364/41532). AF 95% confidence interval is 0.00802. There are 0 homozygotes in gnomad4. There are 174 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
BS2
High Homozygotes in GnomAdExome4 at 3 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.92537T>C p.Val30846Ala missense_variant Exon 339 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.92537T>C p.Val30846Ala missense_variant Exon 339 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.00246
AC:
374
AN:
152062
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00877
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000262
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00316
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00192
GnomAD3 exomes
AF:
0.000635
AC:
158
AN:
248862
Hom.:
1
AF XY:
0.000481
AC XY:
65
AN XY:
134996
show subpopulations
Gnomad AFR exome
AF:
0.00956
Gnomad AMR exome
AF:
0.000203
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:
0.0000266
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000250
AC:
365
AN:
1461596
Hom.:
3
Cov.:
35
AF XY:
0.000223
AC XY:
162
AN XY:
727082
show subpopulations
Gnomad4 AFR exome
AF:
0.00968
Gnomad4 AMR exome
AF:
0.000268
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000450
Gnomad4 OTH exome
AF:
0.000398
GnomAD4 genome
AF:
0.00246
AC:
375
AN:
152180
Hom.:
0
Cov.:
33
AF XY:
0.00234
AC XY:
174
AN XY:
74406
show subpopulations
Gnomad4 AFR
AF:
0.00876
Gnomad4 AMR
AF:
0.000262
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.00190
Alfa
AF:
0.000430
Hom.:
0
Bravo
AF:
0.00271
ESP6500AA
AF:
0.00804
AC:
31
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000836
AC:
101
Asia WGS
AF:
0.000577
AC:
2
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:19
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Benign:6
-
Clinical Genetics, Academic Medical Center
Significance: Benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Aug 17, 2015
Eurofins Ntd Llc (ga)
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance: Benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jan 09, 2012
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Val28278Ala in exon 288 of TTN: This variant is not expected to have clinical si gnificance because it is not located within the splice consensus sequence and ha s been identified in 0.3% (6/2000) of racially unspecified chromosomes (dbSNP rs 77968867) and in 0.8% (27/3168) of African American chromosomes (NHLBI Exome Seq uencing Project; http://evs.gs.washington.edu/EVS) from two broad, though clinic ally unspecified populations. Val28278Ala in exon 288 of TTN (rs7796886, NHLBI Exome Seq Project; 0.8%, 27/3168) -

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

- -

Aug 17, 2020
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.84833T>C (p.Val28278Ala) results in a non-conservative amino acid change located in the A-band of the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.00063 in 248862 control chromosomes in the gnomAD database, including 1 homozygotes. The observed variant frequency is approximately 2 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 benign. To our knowledge, no occurrence of c.84833T>C in individuals affected with Dilated Cardiomyopathy and no experimental evidence demonstrating its impact on protein function have been reported. Co-occurrence with other a pathogenic variant has been reported (TTN c.62134C>T, p.Gln20712X), providing supporting evidence for a benign role. Seven clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation and all laboratories classified this variant as benign/likely benign. Based on the evidence outlined above, the variant was classified as benign. -

not provided Benign:5
Apr 27, 2021
GeneDx
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant is associated with the following publications: (PMID: 23861362) -

Nov 01, 2017
Athena Diagnostics
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

-
Genome Diagnostics Laboratory, University Medical Center Utrecht
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Apr 01, 2024
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J Uncertain:1
Jan 13, 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
Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Cardiomyopathy Benign:1
Aug 03, 2017
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Dilated cardiomyopathy 1G Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance: Likely 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 likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Early-onset myopathy with fatal cardiomyopathy Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance: Likely 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 likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Myopathy, myofibrillar, 9, with early respiratory failure Benign:1
Jan 13, 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 13, 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. -

Primary dilated cardiomyopathy Benign:1
Feb 07, 2018
Center for Advanced Laboratory Medicine, UC San Diego Health, University of California San Diego
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Cardiovascular phenotype Benign:1
Apr 05, 2018
Ambry Genetics
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This alteration is classified as 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
0.11
BayesDel_addAF
Benign
-0.42
T
BayesDel_noAF
Benign
-0.37
CADD
Benign
19
DANN
Uncertain
0.98
Eigen
Benign
-0.13
Eigen_PC
Benign
0.11
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Benign
0.74
T;T;T;.;T;T;T
M_CAP
Benign
0.016
T
MetaRNN
Benign
0.0078
T;T;T;T;T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
0.31
.;.;.;N;.;.;N
PrimateAI
Uncertain
0.69
T
PROVEAN
Benign
-2.2
N;N;.;.;N;N;.
REVEL
Benign
0.22
Sift
Benign
0.41
T;T;.;.;T;T;.
Polyphen
0.0030
.;.;.;B;.;.;B
Vest4
0.45
MVP
0.31
MPC
0.11
ClinPred
0.021
T
GERP RS
5.3

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: rs77968867; hg19: chr2-179413816; COSMIC: COSV104642025; API