rs199652066

Variant summary

Our verdict is Benign. The variant received -16 ACMG points: 0P and 16B. BP4_StrongBP6_Very_StrongBS1

The NM_001267550.2(TTN):​c.12733A>C​(p.Asn4245His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000169 in 1,613,778 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N4245S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0010 ( 1 hom., cov: 32)
Exomes 𝑓: 0.000081 ( 0 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

16

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:16

Conservation

PhyloP100: 0.368

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: Benign. The variant received -16 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.0038260818).
BP6
Variant 2-178740500-T-G is Benign according to our data. Variant chr2-178740500-T-G is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 47829.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 = 0.00102 (155/152292) while in subpopulation AFR AF = 0.00358 (149/41570). AF 95% confidence interval is 0.00312. There are 1 homozygotes in GnomAd4. There are 84 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.12733A>C p.Asn4245His missense_variant Exon 48 of 363 ENST00000589042.5 NP_001254479.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.12733A>C p.Asn4245His missense_variant Exon 48 of 363 5 NM_001267550.2 ENSP00000467141.1

Frequencies

GnomAD3 genomes
AF:
0.000992
AC:
151
AN:
152174
Hom.:
1
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00350
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000327
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:
0.00
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000318
AC:
79
AN:
248494
AF XY:
0.000282
show subpopulations
Gnomad AFR exome
AF:
0.00465
Gnomad AMR exome
AF:
0.000203
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:
0.00
GnomAD4 exome
AF:
0.0000807
AC:
118
AN:
1461486
Hom.:
0
Cov.:
32
AF XY:
0.0000536
AC XY:
39
AN XY:
727020
show subpopulations
African (AFR)
AF:
0.00278
AC:
93
AN:
33474
American (AMR)
AF:
0.000157
AC:
7
AN:
44706
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39634
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53382
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1111784
Other (OTH)
AF:
0.000215
AC:
13
AN:
60356
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
9
18
28
37
46
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
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
GnomAD4 genome
AF:
0.00102
AC:
155
AN:
152292
Hom.:
1
Cov.:
32
AF XY:
0.00113
AC XY:
84
AN XY:
74456
show subpopulations
African (AFR)
AF:
0.00358
AC:
149
AN:
41570
American (AMR)
AF:
0.000327
AC:
5
AN:
15298
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5170
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4818
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68018
Other (OTH)
AF:
0.000473
AC:
1
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.501
Heterozygous variant carriers
0
8
16
23
31
39
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:
0.000443
Hom.:
0
Bravo
AF:
0.00121
ESP6500AA
AF:
0.00463
AC:
18
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000389
AC:
47
Asia WGS
AF:
0.000867
AC:
3
AN:
3476

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:16
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:6
-
Clinical Genetics, Academic Medical Center
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Oct 28, 2016
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 24, 2012
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Asn4007His in exon 45B of TTN: This variant is not expected to have clinical sig nificance because it has been identified in 0.4% (12/3202) of African American c hromosomes by the NHLBI Exome Sequencing Project in a broad population (http://e vs.gs.washington.edu/EVS). Asn4007His in exon 45B of TTN (allele frequency = 0. 4%, 12/3202) ** -

Jan 30, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: TTN c.10361-2140A>C in intron 45, also reported as NM_001267550:c.12733A>C (p.Asn4245His) in exon 48, is located at a position not widely known to affect splicing. Consensus agreement among computation tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 0.00032 in 248494 control chromosomes, predominantly at a frequency of 0.0047 within the African or African-American subpopulation in the gnomAD database. The observed variant frequency within African or African-American control individuals in the gnomAD database is approximately 12-fold of the estimated maximal expected allele frequency for a pathogenic variant in TTN causing Dilated Cardiomyopathy phenotype (0.00039). To our knowledge, no occurrence of c.10361-2140A>C in individuals affected with TTN-related conditions and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 47829). Based on the evidence outlined above, the variant was classified as likely benign. -

Apr 09, 2025
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

BS1;BP6;BP7 -

Aug 21, 2015
Eurofins Ntd Llc (ga)
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:3
Mar 16, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 10, 2021
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J Benign:1
Sep 10, 2021
Genome-Nilou Lab
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

TTN-related disorder Benign:1
Jan 27, 2021
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely 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;C1858763:Dilated cardiomyopathy 1G Benign:1
Jan 29, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Early-onset myopathy with fatal cardiomyopathy Benign:1
Sep 10, 2021
Genome-Nilou Lab
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Tibial muscular dystrophy Benign:1
Sep 10, 2021
Genome-Nilou Lab
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Myopathy, myofibrillar, 9, with early respiratory failure Benign:1
Sep 10, 2021
Genome-Nilou Lab
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Benign:1
Aug 14, 2018
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.090
BayesDel_addAF
Benign
-0.58
T
BayesDel_noAF
Benign
-0.61
CADD
Benign
7.1
DANN
Benign
0.58
Eigen
Benign
-1.1
Eigen_PC
Benign
-1.0
FATHMM_MKL
Benign
0.070
N
LIST_S2
Benign
0.67
T;T;.;T;T;T
M_CAP
Benign
0.019
T
MetaRNN
Benign
0.0038
T;T;T;T;T;T
MetaSVM
Benign
-1.0
T
PhyloP100
0.37
PrimateAI
Benign
0.25
T
PROVEAN
Benign
-1.6
N;.;.;N;N;.
REVEL
Benign
0.030
Sift
Benign
0.23
T;.;.;T;T;.
Vest4
0.086
MVP
0.055
MPC
0.093
ClinPred
0.0066
T
GERP RS
2.6
Mutation Taster
=83/17
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: rs199652066; hg19: chr2-179605227; API