22-19898068-G-A

Position:

chr22-19898068-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2PP3BP4_Moderate

The NM_006440.5(TXNRD2):c.745C>T(p.Arg249Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000182 in 1,563,118 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00019 ( 1 hom. )

Consequence

TXNRD2
NM_006440.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 3.43

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

Multiple lines of computational evidence support a deleterious effect 8: BayesDel_addAF, BayesDel_noAF, Cadd, Dann, M_CAP, MutationAssessor, PROVEAN, REVEL [when max_spliceai, FATHMM_MKL, MetaRNN, MutationTaster, phyloP100way_vertebrate was below the threshold]

BP4

Computational evidence support a benign effect (MetaRNN=0.1320455).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TXNRD2	NM_006440.5 linkuse as main transcript	c.745C>T	p.Arg249Cys	missense_variant	10/18	ENST00000400521.7	NP_006431.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TXNRD2	ENST00000400521.7 linkuse as main transcript	c.745C>T	p.Arg249Cys	missense_variant	10/18	1	NM_006440.5	ENSP00000383365	P4	Q9NNW7-1

Frequencies

GnomAD3 genomes

AF:

0.0000920

AC:

AN:

152218

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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:

0.000188

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000162

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000524

AC:

AN:

171650

Hom.:

AF XY:

0.0000654

AC XY:

AN XY:

91792

show subpopulations

Gnomad AFR exome

AF:

0.000109

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.0000633

Gnomad NFE exome

AF:

0.0000985

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000192

AC:

271

AN:

1410900

Hom.:

Cov.:

AF XY:

0.000195

AC XY:

136

AN XY:

697146

show subpopulations

Gnomad4 AFR exome

AF:

0.0000312

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000548

Gnomad4 SAS exome

AF:

0.0000125

Gnomad4 FIN exome

AF:

0.0000203

Gnomad4 NFE exome

AF:

0.000239

Gnomad4 OTH exome

AF:

0.000103

GnomAD4 genome

AF:

0.0000920

AC:

AN:

152218

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74362

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.000188

Gnomad4 NFE

AF:

0.000162

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000152

Hom.:

Bravo

AF:

0.000102

TwinsUK

AF:

0.000270

AC:

ALSPAC

AF:

0.000259

AC:

ExAC

AF:

0.0000686

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Glucocorticoid deficiency 5

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 11, 2021

- -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jan 02, 2024

Has not been previously published as pathogenic or benign to our knowledge; In silico analysis supports that this missense variant has a deleterious effect on protein structure/function -

Primary dilated cardiomyopathy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 28, 2024

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 249 of the TXNRD2 protein (p.Arg249Cys). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with TXNRD2-related conditions. ClinVar contains an entry for this variant (Variation ID: 390757). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt TXNRD2 protein function with a positive predictive value of 80%. Experimental studies and prediction algorithms are not available or were not evaluated, and the effect of this variant on mRNA splicing is currently unknown. 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

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 03, 2023

The p.R249C variant (also known as c.745C>T), located in coding exon 10 of the TXNRD2 gene, results from a C to T substitution at nucleotide position 745. The arginine at codon 249 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. 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

BayesDel_noAF

Pathogenic

0.25

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.57

.;.;.;.;D;T;.

Eigen

Uncertain

0.62

Eigen_PC

Uncertain

0.41

FATHMM_MKL

Uncertain

0.91

LIST_S2

Pathogenic

0.98

.;D;.;.;D;D;D

M_CAP

Pathogenic

0.36

MetaRNN

Benign

0.13

T;T;T;T;T;T;T

MetaSVM

Uncertain

0.36

MutationAssessor

Pathogenic

4.4

.;.;.;.;H;.;.

MutationTaster

Benign

1.0

D;D;D;D;D;D;D

PrimateAI

Uncertain

0.61

PROVEAN

Pathogenic

-7.9

D;.;D;D;D;.;D

REVEL

Pathogenic

0.66

Sift

Pathogenic

0.0

D;.;D;D;D;.;D

Sift4G

Pathogenic

0.0

D;D;D;D;D;D;D

Polyphen

1.0

.;.;.;.;D;.;D

Vest4

0.82

MVP

0.83

MPC

0.93

ClinPred

1.0

GERP RS

2.2

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.94

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.080

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over