NM_001267550.2:c.71723G>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4_ModerateBP6

The NM_001267550.2(TTN):​c.71723G>A​(p.Gly23908Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000267 in 1,613,396 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: 𝑓 0.00020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000089 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

9
4
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:2O:1

Conservation

PhyloP100: 7.86

Publications

1 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 -3 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.19503105).
BP6
Variant 2-178574409-C-T is Benign according to our data. Variant chr2-178574409-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 179862.

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

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
NM_001267550.2
MANE Select
c.71723G>Ap.Gly23908Asp
missense
Exon 326 of 363NP_001254479.2
TTN
NM_001256850.1
c.66800G>Ap.Gly22267Asp
missense
Exon 276 of 313NP_001243779.1
TTN
NM_133378.4
c.64019G>Ap.Gly21340Asp
missense
Exon 275 of 312NP_596869.4

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.71723G>Ap.Gly23908Asp
missense
Exon 326 of 363ENSP00000467141.1
TTN
ENST00000446966.2
TSL:1
c.71567G>Ap.Gly23856Asp
missense
Exon 324 of 361ENSP00000408004.2
TTN
ENST00000436599.2
TSL:1
c.71447G>Ap.Gly23816Asp
missense
Exon 324 of 361ENSP00000405517.2

Frequencies

GnomAD3 genomes
AF:
0.000197
AC:
30
AN:
152036
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000676
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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
GnomAD2 exomes
AF:
0.0000644
AC:
16
AN:
248338
AF XY:
0.0000817
show subpopulations
Gnomad AFR exome
AF:
0.000776
Gnomad AMR exome
AF:
0.000116
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:
0.00000890
AC:
13
AN:
1461242
Hom.:
0
Cov.:
38
AF XY:
0.00000688
AC XY:
5
AN XY:
726890
show subpopulations
African (AFR)
AF:
0.000299
AC:
10
AN:
33452
American (AMR)
AF:
0.0000671
AC:
3
AN:
44710
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26102
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39684
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86212
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53368
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5760
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111606
Other (OTH)
AF:
0.00
AC:
0
AN:
60348
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.000197
AC:
30
AN:
152154
Hom.:
0
Cov.:
32
AF XY:
0.000309
AC XY:
23
AN XY:
74388
show subpopulations
African (AFR)
AF:
0.000674
AC:
28
AN:
41530
American (AMR)
AF:
0.000131
AC:
2
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5148
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67970
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
2
4
7
9
11
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:
0.000165
Hom.:
0
Bravo
AF:
0.000223
ExAC
AF:
0.0000745
AC:
9

ClinVar

ClinVar submissions as Germline
Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
2
1
not provided (4)
-
2
-
not specified (2)
-
1
-
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 (1)
-
-
1
Cardiovascular phenotype (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.97
BayesDel_addAF
Benign
-0.082
T
BayesDel_noAF
Uncertain
0.010
CADD
Benign
22
DANN
Benign
0.88
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.92
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.98
D
M_CAP
Uncertain
0.20
D
MetaRNN
Benign
0.20
T
MetaSVM
Uncertain
0.61
D
MutationAssessor
Pathogenic
4.2
H
PhyloP100
7.9
PrimateAI
Uncertain
0.76
T
PROVEAN
Pathogenic
-5.4
D
REVEL
Pathogenic
0.83
Sift
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.54
MVP
0.54
MPC
0.53
ClinPred
0.26
T
GERP RS
5.5
Mutation Taster
=37/63
disease causing

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: rs540161344; hg19: chr2-179439136; API