rs186232617

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.38323C>T​(p.Leu12775Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000845 in 1,599,628 control chromosomes in the GnomAD database, including 61 homozygotes. In-silico tool predicts a benign outcome for this variant. 9/11 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0046 ( 20 hom., cov: 22)
Exomes 𝑓: 0.00046 ( 41 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

7

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:8

Conservation

PhyloP100: 0.872

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]

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=0.005691856).
BP6
Variant 2-178654265-G-A is Benign according to our data. Variant chr2-178654265-G-A is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 238762.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 = 0.00463 (689/148938) while in subpopulation AFR AF = 0.0164 (672/40860). AF 95% confidence interval is 0.0154. There are 20 homozygotes in GnomAd4. There are 291 alleles in the male GnomAd4 subpopulation. Median coverage is 22. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 20 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.38323C>T p.Leu12775Phe missense_variant Exon 193 of 363 ENST00000589042.5 NP_001254479.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.38323C>T p.Leu12775Phe missense_variant Exon 193 of 363 5 NM_001267550.2 ENSP00000467141.1

Frequencies

GnomAD3 genomes
AF:
0.00461
AC:
686
AN:
148824
Hom.:
20
Cov.:
22
show subpopulations
Gnomad AFR
AF:
0.0164
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000709
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:
0.0000148
Gnomad OTH
AF:
0.00290
GnomAD2 exomes
AF:
0.00112
AC:
268
AN:
238422
AF XY:
0.000782
show subpopulations
Gnomad AFR exome
AF:
0.0173
Gnomad AMR exome
AF:
0.000486
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000276
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000457
AC:
663
AN:
1450690
Hom.:
41
Cov.:
32
AF XY:
0.000376
AC XY:
271
AN XY:
721488
show subpopulations
African (AFR)
AF:
0.0170
AC:
568
AN:
33374
American (AMR)
AF:
0.000537
AC:
23
AN:
42850
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26092
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39666
South Asian (SAS)
AF:
0.0000478
AC:
4
AN:
83650
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
49128
Middle Eastern (MID)
AF:
0.000354
AC:
2
AN:
5644
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1110196
Other (OTH)
AF:
0.00102
AC:
61
AN:
60090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.439
Heterozygous variant carriers
0
37
73
110
146
183
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
20
40
60
80
100
<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:
0.00463
AC:
689
AN:
148938
Hom.:
20
Cov.:
22
AF XY:
0.00402
AC XY:
291
AN XY:
72402
show subpopulations
African (AFR)
AF:
0.0164
AC:
672
AN:
40860
American (AMR)
AF:
0.000709
AC:
10
AN:
14110
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3462
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5090
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4296
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10302
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000148
AC:
1
AN:
67532
Other (OTH)
AF:
0.00287
AC:
6
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.495
Heterozygous variant carriers
0
31
61
92
122
153
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
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:
0.00180
Hom.:
0
Bravo
AF:
0.00526
ExAC
AF:
0.00139
AC:
166

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:2
Oct 17, 2024
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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

- -

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
Oct 22, 2024
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

- -

not provided Benign:1
Jul 15, 2018
GeneDx
Significance:Likely 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

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Benign
-0.35
T
BayesDel_noAF
Benign
-0.63
CADD
Benign
12
DANN
Benign
0.86
FATHMM_MKL
Benign
0.070
N
LIST_S2
Benign
0.28
T
MetaRNN
Benign
0.0057
T
PhyloP100
0.87
Vest4
0.16
MVP
0.67
GERP RS
-0.94
Mutation Taster
=97/3
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: rs186232617; hg19: chr2-179518992; API