rs1553820518

Variant names:

• chr3-48467484-A-T
• rs1553820518
• NM_033629.6:c.829A>T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The NM_033629.6(TREX1):​c.829A>T​(p.Lys277*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: TREX1 NM_033629.6 stop_gained
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: -1.89

Genes affected

TREX1 (HGNC:12269): (three prime repair exonuclease 1) This gene encodes a nuclear protein with 3' exonuclease activity. The encoded protein may play a role in DNA repair and serve as a proofreading function for DNA polymerase. Mutations in this gene result in Aicardi-Goutieres syndrome, chilblain lupus, Cree encephalitis, and other diseases of the immune system. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2012]

ATRIP (HGNC:33499): (ATR interacting protein) This gene encodes an essential component of the DNA damage checkpoint. The encoded protein binds to single-stranded DNA coated with replication protein A. The protein also interacts with the ataxia telangiectasia and Rad3 related protein kinase, resulting in its accumulation at intranuclear foci induced by DNA damage. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Aug 2012]

ATRIP-TREX1 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.123 CDS is truncated, and there are 2 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 3-48467484-A-T is Pathogenic according to our data. Variant chr3-48467484-A-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 535846.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TREX1	NM_033629.6	c.829A>T	p.Lys277*	stop_gained	Exon 2 of 2	ENST00000625293.3	NP_338599.1
ATRIP	NM_130384.3	c.*1930A>T		3_prime_UTR_variant	Exon 13 of 13	ENST00000320211.10	NP_569055.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TREX1	ENST00000625293.3	c.829A>T	p.Lys277*	stop_gained	Exon 2 of 2	6	NM_033629.6	ENSP00000486676.2
ATRIP	ENST00000320211.10	c.*1930A>T		3_prime_UTR_variant	Exon 13 of 13	1	NM_130384.3	ENSP00000323099.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Chilblain lupus 1;C0796126:Aicardi-Goutieres syndrome 1;C1860518:Retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations Pathogenic:1

Sep 24, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change results in a premature translational stop signal in the TREX1 gene (p.Lys277*). While this is not anticipated to result in nonsense mediated decay, it is expected to delete the last 38 amino acids of the TREX1 protein. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with TREX1-related disease. Different truncating variants downstream from this codon (c.850dupA, c.858dupG, 830_833dup) have been reported in multiple individuals affected with retinal vasculopathy with cerebral leukodystrophy (HERNS syndrome) (PMID: 17660820, 26691497). Experimental studies have shown that these truncated proteins retain exonuclease activity but lose normal perinuclear localization (PMID: 17660820). This suggests that the C-terminal sequence is critical for TREX1 protein function. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.60	D
BayesDel_noAF	Uncertain	0.030
CADD	Benign	23
DANN	Benign	0.86
Eigen	Benign	-0.55
Eigen_PC	Benign	-0.97
FATHMM_MKL	Benign	0.055	N
Vest4		0.82
GERP RS		-6.6

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

Other links and lift over

dbSNP: rs1553820518; hg19: chr3-48508883;