chr2-178768016-G-C

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 1P and 2B. PP2BP4_Moderate

The NM_001267550.2(TTN):ā€‹c.9303C>Gā€‹(p.Asp3101Glu) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000149 in 1,614,006 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/20 in silico tools predict a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (ā˜…ā˜…).

Frequency

Genomes: š‘“ 0.000013 ( 0 hom., cov: 33)
Exomes š‘“: 0.000015 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense, splice_region

Scores

1
16
Splicing: ADA: 0.0001226
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 0.378
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.

PP2
Missense variant in gene, where missense usually causes diseases (based on misZ statistic), TTN. . Gene score misZ -1.1021 (greater than the threshold 3.09). Trascript score misZ 6.9794 (greater than threshold 3.09). GenCC has associacion of gene with dilated cardiomyopathy, tibial muscular dystrophy, early-onset myopathy with fatal cardiomyopathy, autosomal recessive centronuclear myopathy, hypertrophic cardiomyopathy, hypertrophic cardiomyopathy 9, TTN-related myopathy, dilated cardiomyopathy 1G, arrhythmogenic right ventricular cardiomyopathy, myopathy, myofibrillar, 9, with early respiratory failure, familial isolated dilated cardiomyopathy, childhood-onset progressive contractures-limb-girdle weakness-muscle dystrophy syndrome, autosomal recessive limb-girdle muscular dystrophy type 2J.
BP4
Computational evidence support a benign effect (MetaRNN=0.2015787).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
TTNNM_001267550.2 linkuse as main transcriptc.9303C>G p.Asp3101Glu missense_variant, splice_region_variant 39/363 ENST00000589042.5
TTNNM_133379.5 linkuse as main transcriptc.9303C>G p.Asp3101Glu missense_variant, splice_region_variant 39/46 ENST00000360870.10

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
TTNENST00000589042.5 linkuse as main transcriptc.9303C>G p.Asp3101Glu missense_variant, splice_region_variant 39/3635 NM_001267550.2 P1
TTNENST00000360870.10 linkuse as main transcriptc.9303C>G p.Asp3101Glu missense_variant, splice_region_variant 39/465 NM_133379.5 Q8WZ42-6
TTN-AS1ENST00000659121.1 linkuse as main transcriptn.1592+3648G>C intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152184
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000119
AC:
3
AN:
251168
Hom.:
0
AF XY:
0.00000737
AC XY:
1
AN XY:
135734
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:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000150
AC:
22
AN:
1461822
Hom.:
0
Cov.:
36
AF XY:
0.0000151
AC XY:
11
AN XY:
727216
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:
0.0000187
Gnomad4 NFE exome
AF:
0.0000171
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152184
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74330
show subpopulations
Gnomad4 AFR
AF:
0.00
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:
0.0000294
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000113
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpFeb 26, 2016- -
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
Uncertain significance, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsNov 11, 2021- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.17
BayesDel_addAF
Benign
-0.25
T
BayesDel_noAF
Benign
-0.54
CADD
Benign
16
DANN
Benign
0.45
Eigen
Benign
-0.56
Eigen_PC
Benign
-0.45
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Benign
0.71
T;T;T;.;T;T;T;T
M_CAP
Benign
0.011
T
MetaRNN
Benign
0.20
T;T;T;T;T;T;T;T
MetaSVM
Benign
-0.95
T
MutationTaster
Benign
0.99
N;N;N;N;N;N;N
PrimateAI
Benign
0.47
T
PROVEAN
Benign
-2.2
N;N;.;.;N;N;.;N
REVEL
Benign
0.070
Sift
Benign
0.74
T;T;.;.;T;T;.;T
Sift4G
Benign
0.32
.;.;.;.;.;.;.;T
Polyphen
0.0030, 0.031
.;.;.;B;.;.;B;B
Vest4
0.33
MutPred
0.50
Gain of methylation at K3104 (P = 0.0902);.;Gain of methylation at K3104 (P = 0.0902);Gain of methylation at K3104 (P = 0.0902);.;.;Gain of methylation at K3104 (P = 0.0902);Gain of methylation at K3104 (P = 0.0902);
MVP
0.072
MPC
0.081
ClinPred
0.029
T
GERP RS
1.8

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.00012
dbscSNV1_RF
Benign
0.024
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: rs148676491; hg19: chr2-179632743; API