6-123279055-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PVS1_ModerateBS1_Supporting

The NM_006073.4(TRDN):​c.1537+1G>A variant causes a splice donor, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000939 in 1,607,502 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000082 ( 1 hom. )

Consequence

TRDN
NM_006073.4 splice_donor, intron

Scores

3
2
2
Splicing: ADA: 1.000
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7

Conservation

PhyloP100: 1.23

Publications

1 publications found
Variant links:
Genes affected
TRDN (HGNC:12261): (triadin) This gene encodes an integral membrane protein found in skeletal and cardiac muscle. The encoded protein plays a role in skeletal muscle excitation-contraction coupling as part of the calcium release complex and is required for normal skeletal muscle strength. This protein indirectly links triads and microtubules in skeletal muscle. Mutations in this gene are associated with cardiac arrythmia syndrome and some variants in this gene may be associated with sudden cardiac death. [provided by RefSeq, May 2022]
TRDN Gene-Disease associations (from GenCC):
  • catecholaminergic polymorphic ventricular tachycardia
    Inheritance: AD, AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
  • catecholaminergic polymorphic ventricular tachycardia 5
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp
  • familial long QT syndrome
    Inheritance: AR Classification: STRONG Submitted by: G2P
  • long QT syndrome
    Inheritance: AR Classification: STRONG Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.012328767 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
BS1
Variant frequency is greater than expected in population afr. GnomAdExome4 allele frequency = 0.0000824 (120/1455556) while in subpopulation AFR AF = 0.00126 (42/33336). AF 95% confidence interval is 0.000957. There are 1 homozygotes in GnomAdExome4. There are 64 alleles in the male GnomAdExome4 subpopulation. Median coverage is 30. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TRDNNM_006073.4 linkc.1537+1G>A splice_donor_variant, intron_variant Intron 25 of 40 ENST00000334268.9 NP_006064.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TRDNENST00000334268.9 linkc.1537+1G>A splice_donor_variant, intron_variant Intron 25 of 40 1 NM_006073.4 ENSP00000333984.5

Frequencies

GnomAD3 genomes
AF:
0.000198
AC:
30
AN:
151828
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000605
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000657
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000194
Gnomad SAS
AF:
0.000415
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000143
AC:
35
AN:
245594
AF XY:
0.000143
show subpopulations
Gnomad AFR exome
AF:
0.000782
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000170
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000108
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000824
AC:
120
AN:
1455556
Hom.:
1
Cov.:
30
AF XY:
0.0000884
AC XY:
64
AN XY:
723944
show subpopulations
African (AFR)
AF:
0.00126
AC:
42
AN:
33336
American (AMR)
AF:
0.0000451
AC:
2
AN:
44340
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26000
East Asian (EAS)
AF:
0.0000763
AC:
3
AN:
39334
South Asian (SAS)
AF:
0.000188
AC:
16
AN:
85088
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52774
Middle Eastern (MID)
AF:
0.000542
AC:
3
AN:
5536
European-Non Finnish (NFE)
AF:
0.0000397
AC:
44
AN:
1109056
Other (OTH)
AF:
0.000166
AC:
10
AN:
60092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.446
Heterozygous variant carriers
0
6
11
17
22
28
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.000204
AC:
31
AN:
151946
Hom.:
0
Cov.:
32
AF XY:
0.000189
AC XY:
14
AN XY:
74246
show subpopulations
African (AFR)
AF:
0.000627
AC:
26
AN:
41454
American (AMR)
AF:
0.0000656
AC:
1
AN:
15234
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000194
AC:
1
AN:
5154
South Asian (SAS)
AF:
0.000416
AC:
2
AN:
4810
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10546
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67958
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.487
Heterozygous variant carriers
0
2
3
5
6
8
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:
0.000132
Hom.:
0
Bravo
AF:
0.000272
ESP6500AA
AF:
0.000275
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000157
AC:
19
Asia WGS
AF:
0.000578
AC:
2
AN:
3474

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:7
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:3
Jul 22, 2021
AiLife Diagnostics, AiLife Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 26, 2021
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Has not been previously published as pathogenic or benign to our knowledge -

-
Breakthrough Genomics, Breakthrough Genomics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

not specified Uncertain:1
Feb 27, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: TRDN c.1537+1G>A is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: Three predict the variant abolishes a 5' splicing donor site. However, the main TRDN isoform expressed in the heart (NM_001256021.1) is not impacted by this alteration and these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 0.00014 in 245594 control chromosomes in the gnomAD database, including 1 homozygote. This frequency is not significantly higher than estimated for a pathogenic variant in TRDN causing Catecholaminergic Polymorphic Ventricular Tachycardia (0.00014 vs 0.0016), allowing no conclusion about variant significance. To our knowledge, no occurrence of c.1537+1G>A in individuals affected with Catecholaminergic Polymorphic Ventricular Tachycardia and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 408727). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Catecholaminergic polymorphic ventricular tachycardia 1;C3809536:Catecholaminergic polymorphic ventricular tachycardia 5 Uncertain:1
Apr 04, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Catecholaminergic polymorphic ventricular tachycardia 1 Uncertain:1
Dec 06, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change falls in intron 25 of the TRDN gene. It does not directly change the encoded amino acid sequence of the TRDN protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs189125299, gnomAD 0.08%), including at least one homozygous and/or hemizygous individual. This variant has not been reported in the literature in individuals affected with TRDN-related conditions. ClinVar contains an entry for this variant (Variation ID: 408727). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Cardiovascular phenotype Uncertain:1
Sep 18, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1537+1G>A intronic variant results from a G to A substitution one nucleotide after coding exon 25 of the TRDN gene. This nucleotide position is well conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice donor site. Alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. However, this alteration does not impact the predominant cardiac isoform of TRDN (NM_001256021.1; Kobayashi YM et al. J. Biol. Chem., 1999 Oct;274:28660-8). Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.34
D
BayesDel_noAF
Pathogenic
0.22
CADD
Pathogenic
27
DANN
Uncertain
0.97
Eigen
Pathogenic
0.84
Eigen_PC
Uncertain
0.63
FATHMM_MKL
Benign
0.72
D
PhyloP100
1.2
GERP RS
3.5
Mutation Taster
=12/88
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.96
SpliceAI score (max)
0.50
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.50
Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs189125299; hg19: chr6-123600200; API