rs375742678

Variant summary

Our verdict is Benign. The variant received -14 ACMG points: 0P and 14B. BP4_ModerateBP6_Very_StrongBS1

The NM_001267550.2(TTN):​c.32555-6T>C variant causes a splice region, intron change. The variant allele was found at a frequency of 0.000211 in 1,613,412 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0011 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00011 ( 0 hom. )

Consequence

TTN
NM_001267550.2 splice_region, intron

Scores

2
Splicing: ADA: 0.0002844
2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:11

Conservation

PhyloP100: 5.18

Publications

0 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]

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ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -14 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.45).
BP6
Variant 2-178684755-A-G is Benign according to our data. Variant chr2-178684755-A-G is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 46870.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 = 0.00115 (175/152254) while in subpopulation AFR AF = 0.00407 (169/41552). AF 95% confidence interval is 0.00357. There are 0 homozygotes in GnomAd4. There are 77 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

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.32555-6T>C
splice_region intron
N/ANP_001254479.2
TTN
NM_001256850.1
c.31604-6T>C
splice_region intron
N/ANP_001243779.1
TTN
NM_133378.4
c.28823-6T>C
splice_region intron
N/ANP_596869.4

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTN
ENST00000589042.5
TSL:5 MANE Select
c.32555-6T>C
splice_region intron
N/AENSP00000467141.1
TTN
ENST00000446966.2
TSL:1
c.32555-6T>C
splice_region intron
N/AENSP00000408004.2
TTN
ENST00000436599.2
TSL:1
c.32279-6T>C
splice_region intron
N/AENSP00000405517.2

Frequencies

GnomAD3 genomes
AF:
0.00114
AC:
174
AN:
152136
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00406
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000196
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:
0.000955
GnomAD2 exomes
AF:
0.000245
AC:
61
AN:
248676
AF XY:
0.000163
show subpopulations
Gnomad AFR exome
AF:
0.00362
Gnomad AMR exome
AF:
0.0000871
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:
0.000113
AC:
165
AN:
1461158
Hom.:
0
Cov.:
31
AF XY:
0.0000963
AC XY:
70
AN XY:
726832
show subpopulations
African (AFR)
AF:
0.00440
AC:
147
AN:
33430
American (AMR)
AF:
0.000134
AC:
6
AN:
44688
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26116
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39674
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86136
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53386
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1111604
Other (OTH)
AF:
0.000166
AC:
10
AN:
60358
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
7
14
22
29
36
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:
0.00115
AC:
175
AN:
152254
Hom.:
0
Cov.:
32
AF XY:
0.00103
AC XY:
77
AN XY:
74454
show subpopulations
African (AFR)
AF:
0.00407
AC:
169
AN:
41552
American (AMR)
AF:
0.000196
AC:
3
AN:
15294
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
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:
67990
Other (OTH)
AF:
0.000945
AC:
2
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
8
15
23
30
38
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:
0.000923
Hom.:
0
Bravo
AF:
0.00128
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:11
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:5
Apr 18, 2012
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

28823-6T>C in intron 127 of TTN: This variant is not expected to have clinical s ignificance because it has been identified in 0.4% (12/2952) of African American chromosomes from a broad population by the NHLBI Exome Sequencing Project (http ://evs.gs.washington.edu/EVS). 28823-6T>C in intron 127 of TTN (allele frequenc y = 0.4%, 12/2952) **

Oct 23, 2017
GeneDx
Significance:Likely 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.

Jul 29, 2015
Eurofins Ntd Llc (ga)
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Feb 17, 2020
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Jul 24, 2025
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

BS1

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

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Benign:1
Jan 30, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: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

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
Sep 03, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Likely 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

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

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.45
CADD
Benign
15
DANN
Benign
0.82
PhyloP100
5.2
Mutation Taster
=55/45
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.00028
dbscSNV1_RF
Benign
0.030
SpliceAI score (max)
0.080
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: rs375742678; hg19: chr2-179549482; API