rs879048717

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 0P and 1B. BP4

The NM_001267550.2(TTN):​c.107290G>T​(p.Ala35764Ser) variant causes a missense change. The variant allele was found at a frequency of 0.0000171 in 1,461,634 control chromosomes in the GnomAD database, with no homozygous occurrence. 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 Uncertain significance (★★).

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.000017 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

7
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 5.90
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 -1 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.28456748).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.107290G>T p.Ala35764Ser missense_variant Exon 361 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.107290G>T p.Ala35764Ser missense_variant Exon 361 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD3 exomes
AF:
0.00000401
AC:
1
AN:
249116
Hom.:
0
AF XY:
0.00000740
AC XY:
1
AN XY:
135148
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000886
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000171
AC:
25
AN:
1461634
Hom.:
0
Cov.:
31
AF XY:
0.0000124
AC XY:
9
AN XY:
727094
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
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:
0.0000225
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
33
Alfa
AF:
0.0000413
Hom.:
0
Bravo
AF:
0.00000378
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Jan 24, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: TTN c.99586G>T (p.Ala33196Ser) results in a conservative amino acid change located in the M-band of the encoded protein sequence. Two of four in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 249116 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.99586G>T has been reported in the literature in individuals affected with HCM without strong evidence for causality (Thomson_2018). 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. One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Jan 23, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 35764 of the TTN protein (p.Ala35764Ser). This variant is present in population databases (no rsID available, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with TTN-related conditions. ClinVar contains an entry for this variant (Variation ID: 534983). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. This variant is located in the M band of TTN (PMID: 25589632). Non-truncating variants in this region may be relevant for neuromuscular disorders, but have not been definitively shown to cause cardiomyopathy (PMID: 23975875). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1838244:Tibial muscular dystrophy;C1858763:Dilated cardiomyopathy 1G;C1861065:Hypertrophic cardiomyopathy 9;C1863599:Myopathy, myofibrillar, 9, with early respiratory failure;C2673677:Early-onset myopathy with fatal cardiomyopathy Uncertain:1
Jul 07, 2021
Fulgent Genetics, Fulgent Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.24
BayesDel_addAF
Benign
-0.0060
T
BayesDel_noAF
Benign
-0.25
CADD
Benign
18
DANN
Benign
0.84
Eigen
Uncertain
0.61
Eigen_PC
Uncertain
0.62
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.90
D;D;D;.;D;D;D
M_CAP
Benign
0.051
D
MetaRNN
Benign
0.28
T;T;T;T;T;T;T
MetaSVM
Uncertain
-0.13
T
MutationAssessor
Benign
1.7
.;.;.;L;.;.;L
PrimateAI
Benign
0.46
T
PROVEAN
Benign
-2.1
N;N;.;.;N;N;.
REVEL
Uncertain
0.43
Sift
Uncertain
0.019
.;D;.;.;D;D;.
Polyphen
1.0
.;.;.;D;.;.;D
Vest4
0.30
MutPred
0.58
.;.;.;Gain of disorder (P = 0.0179);.;.;Gain of disorder (P = 0.0179);
MVP
0.34
MPC
0.40
ClinPred
0.71
D
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: rs879048717; hg19: chr2-179393088; API