rs200350579

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.84461C>T​(p.Pro28154Leu) variant causes a missense change. The variant allele was found at a frequency of 0.000377 in 1,606,676 control chromosomes in the GnomAD database, including 4 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. P28154P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0022 ( 1 hom., cov: 33)
Exomes 𝑓: 0.00019 ( 3 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

1
6
10

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:17

Conservation

PhyloP100: 3.92

Publications

1 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=0.009172052).
BP6
Variant 2-178561671-G-A is Benign according to our data. Variant chr2-178561671-G-A is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 47437.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 = 0.00217 (331/152292) while in subpopulation AFR AF = 0.00772 (321/41558). AF 95% confidence interval is 0.00703. There are 1 homozygotes in GnomAd4. There are 153 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High Homozygotes in GnomAdExome4 at 3 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.84461C>T p.Pro28154Leu missense_variant Exon 326 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.84461C>T p.Pro28154Leu missense_variant Exon 326 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.00218
AC:
331
AN:
152176
Hom.:
1
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00775
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000524
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:
0.000955
GnomAD2 exomes
AF:
0.000535
AC:
130
AN:
243108
AF XY:
0.000402
show subpopulations
Gnomad AFR exome
AF:
0.00830
Gnomad AMR exome
AF:
0.0000294
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:
0.000171
GnomAD4 exome
AF:
0.000188
AC:
274
AN:
1454384
Hom.:
3
Cov.:
32
AF XY:
0.000149
AC XY:
108
AN XY:
722678
show subpopulations
African (AFR)
AF:
0.00761
AC:
253
AN:
33252
American (AMR)
AF:
0.000158
AC:
7
AN:
44300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25756
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39492
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85240
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53042
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5728
European-Non Finnish (NFE)
AF:
9.03e-7
AC:
1
AN:
1107562
Other (OTH)
AF:
0.000217
AC:
13
AN:
60012
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
Heterozygous variant carriers
0
19
39
58
78
97
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome 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
GnomAD4 genome
AF:
0.00217
AC:
331
AN:
152292
Hom.:
1
Cov.:
33
AF XY:
0.00205
AC XY:
153
AN XY:
74462
show subpopulations
African (AFR)
AF:
0.00772
AC:
321
AN:
41558
American (AMR)
AF:
0.000523
AC:
8
AN:
15296
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
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:
0.00
AC:
0
AN:
68022
Other (OTH)
AF:
0.000945
AC:
2
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.490
Heterozygous variant carriers
0
19
38
57
76
95
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:
0.000961
Hom.:
3
Bravo
AF:
0.00217
ESP6500AA
AF:
0.00659
AC:
25
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000696
AC:
84
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:17
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:7
-
Clinical Genetics, Academic Medical Center
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

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

p.Pro25586Leu in exon 275 of TTN: This variant is not expected to have clinical significance because it has been identified in 0.85% (83/9754) of African chromo somes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org) . -

Jan 24, 2017
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

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

May 29, 2013
Eurofins Ntd Llc (ga)
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 20, 2024
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.76757C>T (p.Pro25586Leu) results in a non-conservative amino acid change located in the A-band region of the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.00053 in 243108 control chromosomes, predominantly at a frequency of 0.0083 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 13-fold of the estimated maximal expected allele frequency for a pathogenic variant in TTN causing Cardiomyopathy phenotype (0.00063), strongly suggesting that the variant is a benign polymorphism found primarily in populations of African or African-American origin. To our knowledge, no occurrence of c.76757C>T in individuals affected with Cardiomyopathy and no experimental evidence demonstrating its impact on protein function have been reported. The following publication have been ascertained in the context of this evaluation (PMID: 27843123). ClinVar contains an entry for this variant (Variation ID: 47437). Based on the evidence outlined above, the variant was classified as likely benign. -

not provided Benign:2
Dec 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

TTN: BS1 -

Mar 02, 2021
GeneDx
Significance:Likely 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
Jan 29, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiomyopathy Benign:1
Jan 09, 2023
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
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

- -

Heart failure Benign:1
Jul 03, 2018
Center for Advanced Laboratory Medicine, UC San Diego Health, University of California San Diego
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

- -

Cardiovascular phenotype Benign:1
Oct 30, 2018
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 v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.099
BayesDel_addAF
Benign
-0.36
T
BayesDel_noAF
Benign
-0.28
CADD
Benign
18
DANN
Benign
0.86
Eigen
Uncertain
0.50
Eigen_PC
Uncertain
0.52
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.90
D;D;D;.;D;D;D
M_CAP
Benign
0.042
D
MetaRNN
Benign
0.0092
T;T;T;T;T;T;T
MetaSVM
Benign
-0.58
T
MutationAssessor
Benign
0.85
.;.;.;L;.;.;L
PhyloP100
3.9
PrimateAI
Uncertain
0.65
T
PROVEAN
Pathogenic
-6.7
D;D;.;.;D;D;.
REVEL
Uncertain
0.32
Sift
Benign
0.36
T;T;.;.;T;T;.
Polyphen
0.93
.;.;.;P;.;.;P
Vest4
0.41
MVP
0.53
MPC
0.26
ClinPred
0.055
T
GERP RS
5.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Mutation Taster
=75/25
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: rs200350579; hg19: chr2-179426398; COSMIC: COSV60025475; COSMIC: COSV60025475; API