rs727504878

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_001267550.2(TTN):​c.47380G>A​(p.Val15794Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000645 in 1,612,452 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V15794D) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000040 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000067 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

16

Clinical Significance

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

Conservation

PhyloP100: -0.690

Publications

5 publications found
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 was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.014852613).
BP6
Variant 2-178617971-C-T is Benign according to our data. Variant chr2-178617971-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 179458.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001267550.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
NM_001267550.2
MANE Select
c.47380G>Ap.Val15794Ile
missense
Exon 253 of 363NP_001254479.2
TTN
NM_001256850.1
c.42457G>Ap.Val14153Ile
missense
Exon 203 of 313NP_001243779.1
TTN
NM_133378.4
c.39676G>Ap.Val13226Ile
missense
Exon 202 of 312NP_596869.4

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.47380G>Ap.Val15794Ile
missense
Exon 253 of 363ENSP00000467141.1
TTN
ENST00000446966.2
TSL:1
c.47224G>Ap.Val15742Ile
missense
Exon 251 of 361ENSP00000408004.2
TTN
ENST00000436599.2
TSL:1
c.47104G>Ap.Val15702Ile
missense
Exon 251 of 361ENSP00000405517.2

Frequencies

GnomAD3 genomes
AF:
0.0000395
AC:
6
AN:
151784
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000195
Gnomad SAS
AF:
0.000830
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000109
AC:
27
AN:
248182
AF XY:
0.000141
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000671
AC:
98
AN:
1460668
Hom.:
0
Cov.:
32
AF XY:
0.000100
AC XY:
73
AN XY:
726646
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33402
American (AMR)
AF:
0.00
AC:
0
AN:
44676
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26090
East Asian (EAS)
AF:
0.000101
AC:
4
AN:
39588
South Asian (SAS)
AF:
0.000997
AC:
86
AN:
86232
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53398
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5758
European-Non Finnish (NFE)
AF:
0.00000630
AC:
7
AN:
1111222
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60302
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.473
Heterozygous variant carriers
0
7
14
21
28
35
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000395
AC:
6
AN:
151784
Hom.:
0
Cov.:
32
AF XY:
0.0000540
AC XY:
4
AN XY:
74114
show subpopulations
African (AFR)
AF:
0.0000242
AC:
1
AN:
41374
American (AMR)
AF:
0.00
AC:
0
AN:
15206
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3462
East Asian (EAS)
AF:
0.000195
AC:
1
AN:
5120
South Asian (SAS)
AF:
0.000830
AC:
4
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67882
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.608
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000227
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ExAC
AF:
0.000116
AC:
14
Asia WGS
AF:
0.000577
AC:
2
AN:
3478

ClinVar

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

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Oct 10, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

not specified Benign:1
Dec 26, 2013
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Val13226Ile in exon 202 of TTN: This variant is not expected to have clinical si gnificance due to a lack of conservation across species, including mammals. Of n ote, more than 10 mammals have an isoleucine (Ile) at this position despite high nearby amino acid conservation. In addition, computational analyses (AlignGVGD, PolyPhen2, SIFT) do not suggest a high likelihood of impact to the protein.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.062
BayesDel_addAF
Benign
-0.55
T
BayesDel_noAF
Benign
-0.63
CADD
Benign
3.9
DANN
Benign
0.80
Eigen
Benign
-1.0
Eigen_PC
Benign
-0.98
FATHMM_MKL
Benign
0.088
N
LIST_S2
Benign
0.80
T
M_CAP
Benign
0.0080
T
MetaRNN
Benign
0.015
T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
-0.035
N
PhyloP100
-0.69
PrimateAI
Benign
0.29
T
PROVEAN
Benign
-0.63
N
REVEL
Benign
0.033
Sift
Benign
0.53
T
Polyphen
0.0020
B
Vest4
0.13
MutPred
0.44
Loss of catalytic residue at V14153 (P = 0.0144)
MVP
0.18
MPC
0.069
ClinPred
0.0089
T
GERP RS
-0.48
Mutation Taster
=97/3
polymorphism

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

Other links and lift over

dbSNP: rs727504878; hg19: chr2-179482698; COSMIC: COSV59991854; COSMIC: COSV59991854; API