rs759474127

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_001267550.2(TTN):​c.90950T>C​(p.Val30317Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000205 in 1,612,656 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: š‘“ 0.000085 ( 0 hom., cov: 33)
Exomes š‘“: 0.000014 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
7
9

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1

Conservation

PhyloP100: 7.31
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 -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.18609121).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.90950T>C p.Val30317Ala missense_variant Exon 335 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.90950T>C p.Val30317Ala missense_variant Exon 335 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.0000854
AC:
13
AN:
152162
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000314
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000241
AC:
6
AN:
248702
Hom.:
0
AF XY:
0.0000222
AC XY:
3
AN XY:
134908
show subpopulations
Gnomad AFR exome
AF:
0.000129
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000137
AC:
20
AN:
1460494
Hom.:
0
Cov.:
33
AF XY:
0.0000151
AC XY:
11
AN XY:
726284
show subpopulations
Gnomad4 AFR exome
AF:
0.000269
Gnomad4 AMR exome
AF:
0.000112
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:
0.00000270
Gnomad4 OTH exome
AF:
0.0000497
GnomAD4 genome
AF:
0.0000854
AC:
13
AN:
152162
Hom.:
0
Cov.:
33
AF XY:
0.0000942
AC XY:
7
AN XY:
74328
show subpopulations
Gnomad4 AFR
AF:
0.000314
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000661
Hom.:
0
Bravo
AF:
0.000106
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3Benign:1
-
Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Nov 14, 2019
GeneDx
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Clinical Genetics, Academic Medical Center
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Dec 21, 2023
Revvity Omics, Revvity
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not specified Uncertain:2
May 30, 2017
Athena Diagnostics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Oct 22, 2015
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.Val27749Ala variant in TTN has not been previously reported in individuals with cardiomyopathy but has been identified in 2/11568 Latino chromosomes and 1 /9802 African chromosomes by the Exome Aggregation Consortium (ExAC, http://exac .broadinstitute.org). Computational prediction tools and conservation analysis d o not provide strong support for or against an impact to the protein. In summary , the clinical significance of the p.Val27749Ala variant is uncertain. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.16
BayesDel_addAF
Benign
-0.23
T
BayesDel_noAF
Benign
-0.33
CADD
Benign
19
DANN
Uncertain
0.98
Eigen
Uncertain
0.23
Eigen_PC
Uncertain
0.39
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Benign
0.82
T;T;T;.;T;T;T
M_CAP
Benign
0.050
D
MetaRNN
Benign
0.19
T;T;T;T;T;T;T
MetaSVM
Benign
-0.56
T
MutationAssessor
Uncertain
2.4
.;.;.;M;.;.;M
PrimateAI
Uncertain
0.50
T
PROVEAN
Uncertain
-2.7
D;D;.;.;D;D;.
REVEL
Benign
0.22
Sift
Uncertain
0.0060
D;D;.;.;D;D;.
Polyphen
0.025
.;.;.;B;.;.;B
Vest4
0.29
MVP
0.55
MPC
0.11
ClinPred
0.15
T
GERP RS
5.8

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: rs759474127; hg19: chr2-179416677; API