chr2-178802247-G-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.186C>T​(p.Arg62Arg) variant causes a synonymous change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000039 in 1,614,024 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 0.000092 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000034 ( 0 hom. )

Consequence

TTN
NM_001267550.2 synonymous

Scores

2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:3

Conservation

PhyloP100: 10.0

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 Gene-Disease associations (from GenCC):
  • dilated cardiomyopathy
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • dilated cardiomyopathy 1G
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P
  • early-onset myopathy with fatal cardiomyopathy
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, G2P
  • TTN-related myopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • myopathy, myofibrillar, 9, with early respiratory failure
    Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, ClinGen, Ambry Genetics
  • tibial muscular dystrophy
    Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen, Orphanet
  • autosomal recessive limb-girdle muscular dystrophy type 2J
    Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet
  • hypertrophic cardiomyopathy 9
    Inheritance: AD Classification: MODERATE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia
  • familial isolated dilated cardiomyopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • autosomal recessive centronuclear myopathy
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • childhood-onset progressive contractures-limb-girdle weakness-muscle dystrophy syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • arrhythmogenic right ventricular cardiomyopathy
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen
  • congenital myopathy
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • hereditary skeletal muscle disorder
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • hypertrophic cardiomyopathy
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen

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 (BayesDel_noAF=-0.27).
BP6
Variant 2-178802247-G-A is Benign according to our data. Variant chr2-178802247-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 196573.

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.186C>Tp.Arg62Arg
synonymous
Exon 3 of 363NP_001254479.2
TTN
NM_001256850.1
c.186C>Tp.Arg62Arg
synonymous
Exon 3 of 313NP_001243779.1
TTN
NM_133378.4
c.186C>Tp.Arg62Arg
synonymous
Exon 3 of 312NP_596869.4

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.186C>Tp.Arg62Arg
synonymous
Exon 3 of 363ENSP00000467141.1
TTN
ENST00000446966.2
TSL:1
c.186C>Tp.Arg62Arg
synonymous
Exon 3 of 361ENSP00000408004.2
TTN
ENST00000436599.2
TSL:1
c.186C>Tp.Arg62Arg
synonymous
Exon 3 of 361ENSP00000405517.2

Frequencies

GnomAD3 genomes
AF:
0.0000921
AC:
14
AN:
152062
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000290
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.000288
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:
0.0000239
AC:
6
AN:
251304
AF XY:
0.0000295
show subpopulations
Gnomad AFR exome
AF:
0.000123
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000335
AC:
49
AN:
1461844
Hom.:
0
Cov.:
32
AF XY:
0.0000399
AC XY:
29
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.000179
AC:
6
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39686
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.0000342
AC:
38
AN:
1111984
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.489
Heterozygous variant carriers
0
3
6
10
13
16
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:
0.0000920
AC:
14
AN:
152180
Hom.:
0
Cov.:
32
AF XY:
0.000121
AC XY:
9
AN XY:
74380
show subpopulations
African (AFR)
AF:
0.000289
AC:
12
AN:
41502
American (AMR)
AF:
0.0000654
AC:
1
AN:
15296
Ashkenazi Jewish (ASJ)
AF:
0.000288
AC:
1
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5172
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68008
Other (OTH)
AF:
0.00
AC:
0
AN:
2108
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.468
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.000107
Hom.:
0
Bravo
AF:
0.0000756
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

ClinVar submissions as Germline
Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
-
1
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G (1)
-
-
1
Cardiomyopathy (1)
-
-
1
Cardiovascular phenotype (1)
-
1
-
not provided (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.27
CADD
Benign
17
DANN
Benign
0.78
PhyloP100
10
Mutation Taster
=1/99
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs528853682; hg19: chr2-179666974; COSMIC: COSV59898801; COSMIC: COSV59898801; API