rs372380420

Variant summary

Our verdict is Benign. Variant got -16 ACMG points: 0P and 16B. BP4_StrongBP6_Very_StrongBS1

The NM_001267550.2(TTN):​c.39296-13C>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000173 in 1,610,666 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.00095 ( 1 hom., cov: 32)
Exomes 𝑓: 0.000091 ( 0 hom. )

Consequence

TTN
NM_001267550.2 intron

Scores

2

Clinical Significance

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

Conservation

PhyloP100: 0.0430
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 made for transcript

Verdict is Benign. Variant got -16 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.54).
BP6
Variant 2-178651980-G-A is Benign according to our data. Variant chr2-178651980-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 178223.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-178651980-G-A is described in Lovd as [Benign]. Variant chr2-178651980-G-A is described in Lovd as [Likely_benign].
BS1
Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.000953 (145/152116) while in subpopulation AFR AF= 0.00328 (136/41516). AF 95% confidence interval is 0.00283. There are 1 homozygotes in gnomad4. There are 71 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.39296-13C>T intron_variant Intron 204 of 362 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.39296-13C>T intron_variant Intron 204 of 362 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000954
AC:
145
AN:
152000
Hom.:
1
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00329
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000459
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00316
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000236
AC:
57
AN:
241980
Hom.:
1
AF XY:
0.000206
AC XY:
27
AN XY:
131308
show subpopulations
Gnomad AFR exome
AF:
0.00359
Gnomad AMR exome
AF:
0.0000592
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000918
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000912
AC:
133
AN:
1458550
Hom.:
0
Cov.:
33
AF XY:
0.0000662
AC XY:
48
AN XY:
725308
show subpopulations
Gnomad4 AFR exome
AF:
0.00353
Gnomad4 AMR exome
AF:
0.0000904
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000270
Gnomad4 OTH exome
AF:
0.000133
GnomAD4 genome
AF:
0.000953
AC:
145
AN:
152116
Hom.:
1
Cov.:
32
AF XY:
0.000955
AC XY:
71
AN XY:
74356
show subpopulations
Gnomad4 AFR
AF:
0.00328
Gnomad4 AMR
AF:
0.000459
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000693
Hom.:
0
Bravo
AF:
0.00100
Asia WGS
AF:
0.000577
AC:
2
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:4
Jul 29, 2015
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

c.31994-13C>T in intron 158 of TTN: This variant is not expected to have clinica l significance because a C>T change at this position does not diverge from the s plice consensus sequence and is therefore unlikely to impact splicing. It has be en identified in 0.3% (26/8354) of African chromosomes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org/; dbSNP rs372380420). -

Aug 24, 2020
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: TTN c.31994-13C>T alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. 4/4 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 0.00024 in 241980 control chromosomes, predominantly at a frequency of 0.0036 within the African or African-American subpopulation in the gnomAD database, including 1 homozygote. The observed variant frequency within African or African-American control individuals in the gnomAD database is approximately 9-fold the estimated maximal expected allele frequency for a pathogenic variant in TTN causing Dilated Cardiomyopathy phenotype (0.00039), 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.31994-13C>T in individuals affected with Dilated Cardiomyopathy and no experimental evidence demonstrating its impact on protein function have been reported. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. Both laboratories cited the variant as benign. Based on the evidence outlined above, the variant was classified as benign. -

Sep 10, 2015
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

- -

not provided Benign:2
-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Mar 08, 2022
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
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

- -

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

- -

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_noAF
Benign
-0.54
CADD
Benign
14
DANN
Benign
0.80

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs372380420; hg19: chr2-179516707; API