8-31141458-G-T

Variant names:

• chr8-31141458-G-T
• rs769665299
• NM_000553.6:c.2996G>T

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000553.6(WRN):​c.2996G>T​(p.Arg999Leu) variant causes a missense change. 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R999H) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: WRN NM_000553.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.72
• Publications: 0 publications found

Genes affected

WRN (HGNC:12791): (WRN RecQ like helicase) This gene encodes a member of the RecQ subfamily of DNA helicase proteins. The encoded nuclear protein is important in the maintenance of genome stability and plays a role in DNA repair, replication, transcription and telomere maintenance. This protein contains a N-terminal 3' to 5' exonuclease domain, an ATP-dependent helicase domain and RQC (RecQ helicase conserved region) domain in its central region, and a C-terminal HRDC (helicase RNase D C-terminal) domain and nuclear localization signal. Defects in this gene are the cause of Werner syndrome, an autosomal recessive disorder characterized by accelerated aging and an elevated risk for certain cancers. [provided by RefSeq, Aug 2017]

WRN Gene-Disease associations (from GenCC):

• Werner syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Orphanet, G2P, Ambry Genetics
• osteosarcoma

  Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.77

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000553.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	WRN	NM_000553.6	MANE Select	c.2996G>T	p.Arg999Leu	missense	Exon 25 of 35	NP_000544.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	WRN	ENST00000298139.7	TSL:1 MANE Select	c.2996G>T	p.Arg999Leu	missense	Exon 25 of 35	ENSP00000298139.5
	WRN	ENST00000521620.5	TSL:1	n.1629G>T		non_coding_transcript_exon	Exon 13 of 23
	WRN	ENST00000650667.1		n.*2610G>T		non_coding_transcript_exon	Exon 24 of 34	ENSP00000498593.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Werner syndrome Uncertain:1

Aug 29, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine with leucine at codon 999 of the WRN protein (p.Arg999Leu). The arginine residue is moderately conserved and there is a moderate physicochemical difference between arginine and leucine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with WRN-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.34
BayesDel_addAF	Benign	-0.060	T
BayesDel_noAF	Benign	-0.32
CADD	Benign	21
DANN	Uncertain	0.99
DEOGEN2	Benign	0.32	T
Eigen	Benign	-0.44
Eigen_PC	Benign	-0.45
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Benign	0.85	T
M_CAP	Benign	0.021	T
MetaRNN	Pathogenic	0.77	D
MetaSVM	Benign	-0.95	T
MutationAssessor	Pathogenic	3.0	M
PhyloP100		4.7
PrimateAI	Benign	0.31	T
PROVEAN	Uncertain	-3.7	D
REVEL	Benign	0.19
Sift	Benign	0.17	T
Sift4G	Benign	0.12	T
Polyphen		0.18	B
Vest4		0.73
MutPred		0.58		Loss of catalytic residue at R999 (P = 0.0212)
MVP		0.43
MPC		0.43
ClinPred		0.98	D
GERP RS		3.0
Varity_R		0.58
gMVP		0.66
Mutation Taster		=57/43	polymorphism

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: rs769665299; hg19: chr8-30998974;