chr22-19933614-C-A

Variant names:

• chr22-19933614-C-A
• rs9605030
• NM_006440.5:c.104-2516G>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_006440.5(TXNRD2):​c.104-2516G>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000155 in 644,216 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000016 (0 hom.)
• Consequence: TXNRD2 NM_006440.5 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.22
• Publications: 0 publications found

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)

ENSG00000289946 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.91).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TXNRD2	NM_006440.5	c.104-2516G>T		intron_variant	Intron 1 of 17	ENST00000400521.7	NP_006431.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TXNRD2	ENST00000400521.7	c.104-2516G>T		intron_variant	Intron 1 of 17	1	NM_006440.5	ENSP00000383365.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000155 AC: 1 AN: 644216 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 323566

⚠️ 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: 13720

American (AMR) AF: 0.00 AC: 0 AN: 16764

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 8530

East Asian (EAS) AF: 0.00 AC: 0 AN: 10022

South Asian (SAS) AF: 0.00 AC: 0 AN: 55548

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10130

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 1658

European-Non Finnish (NFE) AF: 0.00000199 AC: 1 AN: 503510

Other (OTH) AF: 0.00 AC: 0 AN: 24334

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.91
CADD	Benign	0.25
DANN	Benign	0.69
PhyloP100		-1.2
PromoterAI		-0.00010	Neutral

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

Other links and lift over

dbSNP: rs9605030; hg19: chr22-19921137;