rs72677243

Variant summary

Our verdict is Benign. The variant received -9 ACMG points: 0P and 9B. BP4_StrongBP6BS2

The NM_001267550.2(TTN):​c.48953T>C​(p.Ile16318Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00103 in 1,612,356 control chromosomes in the GnomAD database, including 8 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I16318L) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00094 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0010 ( 8 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

6
7
4

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:14

Conservation

PhyloP100: 9.19

Publications

10 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 -9 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.008417815).
BP6
Variant 2-178614561-A-G is Benign according to our data. Variant chr2-178614561-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 47025.
BS2
High Homozygotes in GnomAdExome4 at 8 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.48953T>C p.Ile16318Thr missense_variant Exon 261 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.48953T>C p.Ile16318Thr missense_variant Exon 261 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000955
AC:
145
AN:
151794
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000789
Gnomad ASJ
AF:
0.0110
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000417
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00949
Gnomad NFE
AF:
0.00110
Gnomad OTH
AF:
0.00240
GnomAD2 exomes
AF:
0.00122
AC:
302
AN:
247762
AF XY:
0.00127
show subpopulations
Gnomad AFR exome
AF:
0.000194
Gnomad AMR exome
AF:
0.00111
Gnomad ASJ exome
AF:
0.00997
Gnomad EAS exome
AF:
0.0000565
Gnomad FIN exome
AF:
0.0000931
Gnomad NFE exome
AF:
0.00122
Gnomad OTH exome
AF:
0.00133
GnomAD4 exome
AF:
0.00104
AC:
1513
AN:
1460444
Hom.:
8
Cov.:
34
AF XY:
0.00108
AC XY:
786
AN XY:
726532
show subpopulations
African (AFR)
AF:
0.000269
AC:
9
AN:
33396
American (AMR)
AF:
0.00119
AC:
53
AN:
44626
Ashkenazi Jewish (ASJ)
AF:
0.00954
AC:
249
AN:
26098
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39468
South Asian (SAS)
AF:
0.000592
AC:
51
AN:
86216
European-Finnish (FIN)
AF:
0.0000562
AC:
3
AN:
53358
Middle Eastern (MID)
AF:
0.00139
AC:
8
AN:
5754
European-Non Finnish (NFE)
AF:
0.000958
AC:
1065
AN:
1111234
Other (OTH)
AF:
0.00124
AC:
75
AN:
60294
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
87
173
260
346
433
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
40
80
120
160
200
<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:
0.000941
AC:
143
AN:
151912
Hom.:
0
Cov.:
32
AF XY:
0.000984
AC XY:
73
AN XY:
74216
show subpopulations
African (AFR)
AF:
0.000217
AC:
9
AN:
41502
American (AMR)
AF:
0.000788
AC:
12
AN:
15238
Ashkenazi Jewish (ASJ)
AF:
0.0110
AC:
38
AN:
3462
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5116
South Asian (SAS)
AF:
0.000417
AC:
2
AN:
4796
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10596
Middle Eastern (MID)
AF:
0.00680
AC:
2
AN:
294
European-Non Finnish (NFE)
AF:
0.00110
AC:
75
AN:
67888
Other (OTH)
AF:
0.00237
AC:
5
AN:
2108
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.493
Heterozygous variant carriers
0
7
14
21
28
35
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.00151
Hom.:
3
Bravo
AF:
0.000948
TwinsUK
AF:
0.00108
AC:
4
ALSPAC
AF:
0.00104
AC:
4
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.00182
AC:
15
ExAC
AF:
0.00122
AC:
148
Asia WGS
AF:
0.00115
AC:
4
AN:
3478
EpiCase
AF:
0.00224
EpiControl
AF:
0.00237

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:6Benign:14
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Uncertain:1Benign:4
Mar 09, 2015
Genetic Services Laboratory, University of Chicago
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 12, 2019
Al Jalila Children’s Genomics Center, Al Jalila Childrens Speciality Hospital
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 04, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely 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:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 15, 2016
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant classified as Uncertain Significance - Favor Benign. The p.Ile13750Thr v ariant in TTN has been identified by our laboratory in several individuals with various types of cardiomyopathy, did not segregate with disease in 1 relative wi th HCM, and has been identified in 0.2% (119/66356) of European chromosomes, inc luding 1 homozygote, by the Exome Aggregation Consortium (ExAC, http://exac.broa dinstitute.org; dbSNP rs72677243). Computational prediction tools and conservati on analysis suggest that the p.Ile13750Thr variant may impact the protein, thoug h this information is not predictive enough to determine pathogenicity. In summa ry, while the clinical significance of the p.Ile13750Thr variant is uncertain, i ts frequency suggests that it is more likely to be benign. -

not provided Uncertain:1Benign:4
Sep 04, 2020
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 28144010, 27488758) -

Feb 06, 2018
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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

TTN: BS1, BS2 -

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

- -

Jul 10, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Tibial muscular dystrophy Uncertain:1Benign:1
Jul 07, 2014
Foundation for Research in Genetics and Endocrinology, FRIGE's Institute of Human Genetics
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The observed variant c.22334T>C (p.I7445T) is reported in 1000 Genomes and ExAC databases with a minor allele frequency of 0.0004 and 0.0012 respectively. The in silico prediction of the above variant is disease causing by MutationTaster2, tolerated by SIFT and probably damaging by PolyPhen2. -

May 08, 2017
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Cardiomyopathy Benign:2
Apr 01, 2019
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

- -

Jun 24, 2019
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Early-onset myopathy with fatal cardiomyopathy Uncertain:1
May 08, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Cardiovascular phenotype Uncertain:1
Feb 07, 2013
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

There is insufficient or conflicting evidence for classification of this alteration. -

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

- -

Dilated cardiomyopathy 1G Benign:1
May 08, 2017
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to rule this variant out of causing disease. Therefore, this variant is classified as benign. -

Myopathy, myofibrillar, 9, with early respiratory failure Benign:1
May 08, 2017
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.91
BayesDel_addAF
Benign
-0.095
T
BayesDel_noAF
Uncertain
0.040
CADD
Benign
20
DANN
Benign
0.85
Eigen
Pathogenic
0.89
Eigen_PC
Pathogenic
0.75
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.92
D;D;D;.;D;D;D
M_CAP
Uncertain
0.11
D
MetaRNN
Benign
0.0084
T;T;T;T;T;T;T
MetaSVM
Uncertain
0.76
D
MutationAssessor
Pathogenic
4.0
.;.;.;H;.;.;H
PhyloP100
9.2
PrimateAI
Uncertain
0.62
T
PROVEAN
Uncertain
-3.6
D;D;.;.;D;D;.
REVEL
Pathogenic
0.75
Sift
Uncertain
0.0010
D;D;.;.;D;D;.
Polyphen
0.99
.;.;.;D;.;.;D
Vest4
0.54
MVP
0.87
MPC
0.45
ClinPred
0.40
T
GERP RS
5.6
Mutation Taster
=95/5
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: rs72677243; hg19: chr2-179479288; COSMIC: COSV60286115; COSMIC: COSV60286115; API