22-19877105-T-G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM4

The NM_006440.5(TXNRD2):​c.1575A>C​(p.Ter525Tyrext*?) variant causes a stop lost change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000376 in 1,597,842 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000028 ( 0 hom. )

Consequence

TXNRD2
NM_006440.5 stop_lost

Scores

2
5

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.87

Publications

0 publications found
Variant links:
Genes affected
TXNRD2 (HGNC:18155): (thioredoxin reductase 2) The protein encoded by this gene belongs to the pyridine nucleotide-disulfide oxidoreductase family, and is a member of the thioredoxin (Trx) system. Three thioredoxin reductase (TrxR) isozymes are found in mammals. TrxRs are selenocysteine-containing flavoenzymes, which reduce thioredoxins, as well as other substrates, and play a key role in redox homoeostasis. This gene encodes a mitochondrial form important for scavenging reactive oxygen species in mitochondria. It functions as a homodimer containing FAD, and selenocysteine (Sec) at the active site. Sec is encoded by UGA codon that normally signals translation termination. The 3' UTRs of selenoprotein mRNAs contain a conserved stem-loop structure, the Sec insertion sequence (SECIS) element, which is necessary for the recognition of UGA as a Sec codon rather than as a stop signal. Alternatively spliced transcript variants encoding different isoforms, including a few localized in the cytosol and some lacking the C-terminal Sec residue, have been found for this gene. [provided by RefSeq, Jun 2017]
TXNRD2 Gene-Disease associations (from GenCC):
  • familial isolated dilated cardiomyopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • familial glucocorticoid deficiency
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • dilated cardiomyopathy
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • glucocorticoid deficiency 5
    Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM4
Stoplost variant in NM_006440.5 Downstream stopcodon found after 100 codons.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TXNRD2NM_006440.5 linkc.1575A>C p.Ter525Tyrext*? stop_lost Exon 17 of 18 ENST00000400521.7 NP_006431.2 Q9NNW7-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TXNRD2ENST00000400521.7 linkc.1575A>C p.Ter525Tyrext*? stop_lost Exon 17 of 18 1 NM_006440.5 ENSP00000383365.1 Q9NNW7-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152116
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000408
AC:
1
AN:
245160
AF XY:
0.00000747
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000904
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000277
AC:
4
AN:
1445726
Hom.:
0
Cov.:
31
AF XY:
0.00000279
AC XY:
2
AN XY:
716062
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33216
American (AMR)
AF:
0.00
AC:
0
AN:
44394
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25946
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39240
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85778
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52194
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5688
European-Non Finnish (NFE)
AF:
0.00000364
AC:
4
AN:
1099814
Other (OTH)
AF:
0.00
AC:
0
AN:
59456
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.003763), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152116
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74302
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41418
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
67990
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000113

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Primary dilated cardiomyopathy Uncertain:1
May 22, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. This variant has not been reported in the literature in individuals affected with TXNRD2-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.0009%). This sequence change disrupts the translational stop signal of the TXNRD2 mRNA. It is expected to disrupt the last amino acid of the TXNRD2 protein and extend the protein by an uncertain number of additional amino acid residue(s). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Benign
-0.15
T
BayesDel_noAF
Benign
-0.45
CADD
Benign
12
DANN
Benign
0.74
Eigen
Uncertain
0.30
Eigen_PC
Benign
0.0092
FATHMM_MKL
Uncertain
0.89
D
PhyloP100
1.9
GERP RS
1.0
Mutation Taster
=100/0
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs890339708; hg19: chr22-19864628; API