rs144539321

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_001267550.2(TTN):​c.11311+4071A>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000358 in 1,612,778 control chromosomes in the GnomAD database, including 3 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0018 ( 3 hom., cov: 32)
Exomes 𝑓: 0.00021 ( 0 hom. )

Consequence

TTN
NM_001267550.2 intron

Scores

1
14

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:6O:1

Conservation

PhyloP100: -0.101

Publications

3 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: Benign. The variant received -20 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.0032482743).
BP6
Variant 2-178749053-T-C is Benign according to our data. Variant chr2-178749053-T-C is described in ClinVar as Likely_benign. ClinVar VariationId is 47752.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00178 (271/152094) while in subpopulation AFR AF = 0.00623 (259/41540). AF 95% confidence interval is 0.00561. There are 3 homozygotes in GnomAd4. There are 137 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 3 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.11311+4071A>G intron_variant Intron 47 of 362 ENST00000589042.5 NP_001254479.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.11311+4071A>G intron_variant Intron 47 of 362 5 NM_001267550.2 ENSP00000467141.1

Frequencies

GnomAD3 genomes
AF:
0.00178
AC:
271
AN:
151976
Hom.:
3
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00625
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000460
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:
0.0000147
Gnomad OTH
AF:
0.00192
GnomAD2 exomes
AF:
0.000445
AC:
111
AN:
249558
AF XY:
0.000355
show subpopulations
Gnomad AFR exome
AF:
0.00638
Gnomad AMR exome
AF:
0.000232
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:
0.000331
GnomAD4 exome
AF:
0.000209
AC:
306
AN:
1460684
Hom.:
0
Cov.:
36
AF XY:
0.000187
AC XY:
136
AN XY:
726668
show subpopulations
African (AFR)
AF:
0.00781
AC:
261
AN:
33422
American (AMR)
AF:
0.000247
AC:
11
AN:
44616
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26086
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39608
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86212
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53256
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5756
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1111408
Other (OTH)
AF:
0.000497
AC:
30
AN:
60320
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
18
36
54
72
90
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.00178
AC:
271
AN:
152094
Hom.:
3
Cov.:
32
AF XY:
0.00184
AC XY:
137
AN XY:
74364
show subpopulations
African (AFR)
AF:
0.00623
AC:
259
AN:
41540
American (AMR)
AF:
0.000460
AC:
7
AN:
15230
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5164
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:
0.0000147
AC:
1
AN:
67940
Other (OTH)
AF:
0.00190
AC:
4
AN:
2108
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
13
25
38
50
63
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
4
8
12
16
20
<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:
0.000739
Hom.:
2
Bravo
AF:
0.00193
ESP6500AA
AF:
0.00726
AC:
32
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000602
AC:
73
Asia WGS
AF:
0.000866
AC:
3
AN:
3478

ClinVar

Significance: Likely benign
Submissions summary: Benign:6Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:3
Apr 09, 2025
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jun 12, 2015
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

p.Ile4449Met in exon 45A of TTN: This variant is not expected to have clinical s ignificance because it has been identified in 0.7% (69/9888) of African chromoso mes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; d bSNP rs144539321). -

Dec 30, 2016
Eurofins Ntd Llc (ga)
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

TTN-related disorder Benign:1
Aug 21, 2019
PreventionGenetics, part of Exact Sciences
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

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 Benign:1
Aug 02, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Limb-girdle muscular dystrophy Benign:1
Sep 03, 2019
Cambridge Genomics Laboratory, East Genomic Laboratory Hub, NHS Genomic Medicine Service
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Other:1
Feb 14, 2014
GeneDx
Significance:not provided
Review Status:no classification provided
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Benign
-0.63
T
BayesDel_noAF
Benign
-0.67
CADD
Benign
4.7
DANN
Benign
0.97
Eigen
Benign
-0.68
Eigen_PC
Benign
-0.71
FATHMM_MKL
Benign
0.050
N
LIST_S2
Benign
0.41
T
M_CAP
Benign
0.0061
T
MetaRNN
Benign
0.0032
T
MetaSVM
Benign
-1.1
T
PhyloP100
-0.10
PROVEAN
Benign
-0.56
N
REVEL
Benign
0.053
Sift
Benign
0.20
T
Sift4G
Uncertain
0.023
D
Polyphen
0.68
P
Vest4
0.20
MVP
0.29
ClinPred
0.0017
T
GERP RS
0.81
Mutation Taster
=100/0
polymorphism

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: rs144539321; hg19: chr2-179613780; API