rs55915651

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 1P and 3B. PP2BP4_ModerateBP6

The NM_001267550.2(TTN):​c.97396G>A​(p.Glu32466Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000403 in 1,613,484 control chromosomes in the GnomAD database, including 1 homozygotes. 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 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000040 ( 1 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

3
6
8

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:2

Conservation

PhyloP100: 7.91
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.

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=0.19125563).
BP6
Variant 2-178542360-C-T is Benign according to our data. Variant chr2-178542360-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 229554.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=2}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTNNM_001267550.2 linkuse as main transcriptc.97396G>A p.Glu32466Lys missense_variant 349/363 ENST00000589042.5 NP_001254479.2
TTN-AS1NR_038272.1 linkuse as main transcriptn.2042C>T splice_region_variant, non_coding_transcript_exon_variant 7/17

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkuse as main transcriptc.97396G>A p.Glu32466Lys missense_variant 349/3635 NM_001267550.2 ENSP00000467141 P1
TTN-AS1ENST00000659121.1 linkuse as main transcriptn.416+18724C>T intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes
AF:
0.0000395
AC:
6
AN:
152034
Hom.:
0
Cov.:
32
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:
0.000581
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0000943
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000765
AC:
19
AN:
248238
Hom.:
1
AF XY:
0.0000891
AC XY:
12
AN XY:
134678
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000871
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000672
Gnomad SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000267
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000404
AC:
59
AN:
1461332
Hom.:
1
Cov.:
32
AF XY:
0.0000454
AC XY:
33
AN XY:
726946
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000671
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000404
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.0000562
Gnomad4 NFE exome
AF:
0.0000324
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152152
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74362
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000583
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.0000943
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000143
Hom.:
0
Bravo
AF:
0.0000529
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.0000744
AC:
9
Asia WGS
AF:
0.000289
AC:
1
AN:
3476

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineMar 11, 2015The p.Glu29898Lys variant in TTN has not been previously reported in individuals with cardiomyopathy, but has been identified in 5/8266 East Asian chromosomes b y the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs55915651). Computational prediction tools and conservation analysis do not pro vide strong support for or against an impact to the protein. In summary, the cli nical significance of the p.Glu29898Lys variant is uncertain. -
TTN-related disorder Uncertain:1
Uncertain significance, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesSep 06, 2024The TTN c.97396G>A variant is predicted to result in the amino acid substitution p.Glu32466Lys. To our knowledge, this variant has not been reported in individuals with TTN-associated disorders in the literature. This variant is reported in 0.062% of alleles in individuals of East Asian descent in gnomAD, including 1 homozygote. Although we suspect that this variant may be benign, at this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpApr 29, 2016- -
Cardiomyopathy Benign:1
Likely benign, criteria provided, single submitterclinical testingCHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern OntarioSep 04, 2020- -
not provided Benign:1
Likely benign, criteria provided, single submitterclinical testingGeneDxJun 15, 2018- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.37
BayesDel_addAF
Benign
-0.24
T
BayesDel_noAF
Benign
-0.22
CADD
Uncertain
23
DANN
Uncertain
0.98
Eigen
Pathogenic
0.82
Eigen_PC
Pathogenic
0.85
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.91
D;D;D;.;D;D;D
M_CAP
Benign
0.018
T
MetaRNN
Benign
0.19
T;T;T;T;T;T;T
MetaSVM
Benign
-0.54
T
MutationAssessor
Benign
1.4
.;.;.;L;.;.;L
MutationTaster
Benign
1.0
D;D;D;D;D;D
PrimateAI
Uncertain
0.63
T
PROVEAN
Uncertain
-2.8
D;D;.;.;D;D;.
REVEL
Uncertain
0.43
Sift
Benign
0.11
T;D;.;.;T;T;.
Polyphen
1.0
.;.;.;D;.;.;D
Vest4
0.61
MutPred
0.64
.;.;.;Gain of MoRF binding (P = 9e-04);.;.;Gain of MoRF binding (P = 9e-04);
MVP
0.48
MPC
0.49
ClinPred
0.30
T
GERP RS
6.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.0

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: rs55915651; hg19: chr2-179407087; COSMIC: COSV59910547; COSMIC: COSV59910547; API