rs369933152

Variant summary

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

The NM_001267550.2(TTN):​c.14998C>T​(p.Arg5000Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000714 in 1,611,242 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R5000H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00032 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000046 ( 1 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

3
4
9

Clinical Significance

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

Conservation

PhyloP100: 8.05

Publications

2 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=0.075820684).
BP6
Variant 2-178734926-G-A is Benign according to our data. Variant chr2-178734926-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 46596.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.14998C>T p.Arg5000Cys missense_variant Exon 51 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.14998C>T p.Arg5000Cys missense_variant Exon 51 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000315
AC:
48
AN:
152176
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00104
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.000955
GnomAD2 exomes
AF:
0.0000991
AC:
24
AN:
242204
AF XY:
0.0000761
show subpopulations
Gnomad AFR exome
AF:
0.00139
Gnomad AMR exome
AF:
0.0000296
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000184
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000459
AC:
67
AN:
1458948
Hom.:
1
Cov.:
31
AF XY:
0.0000469
AC XY:
34
AN XY:
725552
show subpopulations
African (AFR)
AF:
0.000867
AC:
29
AN:
33452
American (AMR)
AF:
0.0000678
AC:
3
AN:
44258
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26086
East Asian (EAS)
AF:
0.0000760
AC:
3
AN:
39472
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86028
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53234
Middle Eastern (MID)
AF:
0.000174
AC:
1
AN:
5760
European-Non Finnish (NFE)
AF:
0.0000207
AC:
23
AN:
1110402
Other (OTH)
AF:
0.0000996
AC:
6
AN:
60256
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.462
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
Exome Hom
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:
0.000315
AC:
48
AN:
152294
Hom.:
0
Cov.:
33
AF XY:
0.000363
AC XY:
27
AN XY:
74456
show subpopulations
African (AFR)
AF:
0.00103
AC:
43
AN:
41564
American (AMR)
AF:
0.0000654
AC:
1
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5178
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
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:
0.0000294
AC:
2
AN:
68030
Other (OTH)
AF:
0.000945
AC:
2
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
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

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:
0.000283
Hom.:
0
Bravo
AF:
0.000336
ESP6500AA
AF:
0.000806
AC:
3
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000994
AC:
12

ClinVar

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

Submissions by phenotype

not specified Uncertain:1Benign:1
Jul 19, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: TTN c.11266C>T (p.Arg3756Cys) results in a non-conservative amino acid change located in the I-band of the encoded protein sequence. Three of four in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 9.9e-05 in 242204 control chromosomes, predominantly at a frequency of 0.0014 within the African or African-American subpopulation in the gnomAD database, including 1 homozygotes. The observed variant frequency within African or African-American control individuals in the gnomAD database is approximately 4 fold of the estimated maximal expected allele frequency for a pathogenic variant in TTN causing Dilated Cardiomyopathy phenotype (0.00039), strongly suggesting that the variant is a benign polymorphism found primarily in populations of African or African-American origin. To our knowledge, no occurrence of c.11266C>T in individuals affected with Dilated Cardiomyopathy and no experimental evidence demonstrating its impact on protein function have been reported. Co-occurrences with a pathogenic variant has been reported (TTR c.424G>A, p.Val142Ile), providing supporting evidence for a benign role. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. Both laboratories classified the variant as likely benign. Based on the evidence outlined above, the variant was classified as benign. -

Nov 19, 2012
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The Arg3756Cys variant in TTN has not been reported in the literature nor previo usly identified by our laboratory. This variant has been identified in 3/3724 Af rican American chromosomes from a broad population by the NHLBI Exome Sequencing Project (http://evs.gs.washington.edu/EVS). Computational analyses (biochemical amino acid properties, conservation, AlignGVGD, PolyPhen2, and SIFT) suggest th at this variant may impact the protein, though this information is not predictiv e enough to determine pathogenicity. Additional information is needed to fully a ssess the clinical significance of the Arg3756Cys variant. -

not provided Uncertain:1Benign:1
Nov 13, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 20, 2023
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Benign:1
Feb 03, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.17
BayesDel_addAF
Benign
-0.30
T
BayesDel_noAF
Benign
-0.25
CADD
Pathogenic
26
DANN
Uncertain
0.97
Eigen
Pathogenic
0.90
Eigen_PC
Pathogenic
0.89
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Benign
0.83
T;D;.;D
M_CAP
Benign
0.025
D
MetaRNN
Benign
0.076
T;T;T;T
MetaSVM
Benign
-0.52
T
PhyloP100
8.1
PrimateAI
Uncertain
0.51
T
PROVEAN
Uncertain
-4.1
D;.;.;.
REVEL
Uncertain
0.39
Sift
Benign
0.037
D;.;.;.
Polyphen
1.0
.;.;D;D
Vest4
0.25
MVP
0.53
MPC
0.50
ClinPred
0.10
T
GERP RS
5.9
Mutation Taster
=82/18
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs369933152; hg19: chr2-179599653; COSMIC: COSV104643017; COSMIC: COSV104643017; API