rs56264840

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_001267550.2(TTN):​c.82560C>A​(p.Asn27520Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00211 in 1,613,796 control chromosomes in the GnomAD database, including 47 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 0.0017 ( 5 hom., cov: 33)
Exomes 𝑓: 0.0022 ( 42 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

2
8
5

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:23

Conservation

PhyloP100: 3.30

Publications

13 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 -13 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.0070592165).
BP6
Variant 2-178563572-G-T is Benign according to our data. Variant chr2-178563572-G-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 47414.
BS1
Variant frequency is greater than expected in population sas. GnomAd4 allele frequency = 0.00174 (265/152256) while in subpopulation SAS AF = 0.0232 (112/4826). AF 95% confidence interval is 0.0197. There are 5 homozygotes in GnomAd4. There are 149 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 5 AD,AR gene

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001267550.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
NM_001267550.2
MANE Select
c.82560C>Ap.Asn27520Lys
missense
Exon 326 of 363NP_001254479.2
TTN
NM_001256850.1
c.77637C>Ap.Asn25879Lys
missense
Exon 276 of 313NP_001243779.1
TTN
NM_133378.4
c.74856C>Ap.Asn24952Lys
missense
Exon 275 of 312NP_596869.4

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.82560C>Ap.Asn27520Lys
missense
Exon 326 of 363ENSP00000467141.1
TTN
ENST00000446966.2
TSL:1
c.82404C>Ap.Asn27468Lys
missense
Exon 324 of 361ENSP00000408004.2
TTN
ENST00000436599.2
TSL:1
c.82284C>Ap.Asn27428Lys
missense
Exon 324 of 361ENSP00000405517.2

Frequencies

GnomAD3 genomes
AF:
0.00172
AC:
262
AN:
152138
Hom.:
4
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000169
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00170
Gnomad ASJ
AF:
0.000865
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.0226
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00168
Gnomad OTH
AF:
0.00143
GnomAD2 exomes
AF:
0.00361
AC:
898
AN:
248844
AF XY:
0.00457
show subpopulations
Gnomad AFR exome
AF:
0.000129
Gnomad AMR exome
AF:
0.000840
Gnomad ASJ exome
AF:
0.000895
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00173
Gnomad OTH exome
AF:
0.00347
GnomAD4 exome
AF:
0.00215
AC:
3146
AN:
1461540
Hom.:
42
Cov.:
37
AF XY:
0.00275
AC XY:
1996
AN XY:
727058
show subpopulations
African (AFR)
AF:
0.000329
AC:
11
AN:
33460
American (AMR)
AF:
0.000738
AC:
33
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.000842
AC:
22
AN:
26130
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39684
South Asian (SAS)
AF:
0.0202
AC:
1745
AN:
86258
European-Finnish (FIN)
AF:
0.0000749
AC:
4
AN:
53402
Middle Eastern (MID)
AF:
0.00434
AC:
25
AN:
5766
European-Non Finnish (NFE)
AF:
0.00103
AC:
1142
AN:
1111750
Other (OTH)
AF:
0.00268
AC:
162
AN:
60368
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
237
474
712
949
1186
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
48
96
144
192
240
<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:
0.00174
AC:
265
AN:
152256
Hom.:
5
Cov.:
33
AF XY:
0.00200
AC XY:
149
AN XY:
74432
show subpopulations
African (AFR)
AF:
0.000168
AC:
7
AN:
41554
American (AMR)
AF:
0.00170
AC:
26
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.000865
AC:
3
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5168
South Asian (SAS)
AF:
0.0232
AC:
112
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00168
AC:
114
AN:
68014
Other (OTH)
AF:
0.00142
AC:
3
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.498
Heterozygous variant carriers
0
12
25
37
50
62
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.00155
Hom.:
1
Bravo
AF:
0.00104
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00156
AC:
6
ESP6500AA
AF:
0.000501
AC:
2
ESP6500EA
AF:
0.00180
AC:
15
ExAC
AF:
0.00414
AC:
501
Asia WGS
AF:
0.00953
AC:
33
AN:
3476
EpiCase
AF:
0.00278
EpiControl
AF:
0.00243

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:23
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Benign:8
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

Feb 08, 2016
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease.

Clinical Genetics, Academic Medical Center
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

Nov 05, 2019
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Feb 25, 2015
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

p.Asn24952Lys in exon 275 of TTN: This variant is not expected to have clinical significance because it has been identified in 2.3% (372/16512) of South Asian c hromosomes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute .org; dbSNP rs56264840).

Jan 06, 2020
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

Sep 01, 2015
Eurofins Ntd Llc (ga)
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

not provided Uncertain:1Benign:6
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Likely benign
Review Status:no assertion criteria provided
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

Sep 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

TTN: BS1, BS2

Nov 14, 2024
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Jun 24, 2013
Biesecker Lab/Clinical Genomics Section, National Institutes of Health
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:research

Mar 17, 2014
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Autosomal recessive limb-girdle muscular dystrophy type 2J Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease.

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Benign:1
Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Cardiomyopathy Benign:1
May 30, 2019
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Dilated cardiomyopathy 1G Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease.

Early-onset myopathy with fatal cardiomyopathy Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease.

Myopathy, myofibrillar, 9, with early respiratory failure Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease.

Tibial muscular dystrophy Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease.

Primary dilated cardiomyopathy Benign:1
Feb 28, 2017
Center for Advanced Laboratory Medicine, UC San Diego Health, University of California San Diego
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Cardiovascular phenotype Benign:1
Feb 22, 2017
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as 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 v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.86
BayesDel_addAF
Benign
-0.44
T
BayesDel_noAF
Benign
-0.38
CADD
Benign
16
DANN
Benign
0.92
Eigen
Uncertain
0.45
Eigen_PC
Uncertain
0.38
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.93
D
MetaRNN
Benign
0.0071
T
MetaSVM
Benign
-0.47
T
MutationAssessor
Uncertain
2.5
M
PhyloP100
3.3
PrimateAI
Uncertain
0.66
T
PROVEAN
Pathogenic
-4.6
D
REVEL
Uncertain
0.42
Sift
Uncertain
0.0030
D
Polyphen
1.0
D
Vest4
0.38
MutPred
0.58
Gain of catalytic residue at N25879 (P = 0.0091)
MVP
0.25
MPC
0.50
ClinPred
0.13
T
GERP RS
2.8
Mutation Taster
=74/26
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: rs56264840; hg19: chr2-179428299; API