rs920563936

Positions:

• chr8-31111684-C-A
• chr8-31111684-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000553.6(WRN):​c.2158C>A​(p.Leu720Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 13/21 in silico tools predict a benign 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. L720Q) 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: 0.633

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
WRN	NM_000553.6	c.2158C>A	p.Leu720Met	missense_variant	19/35	ENST00000298139.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
WRN	ENST00000298139.7	c.2158C>A	p.Leu720Met	missense_variant	19/35	1	NM_000553.6	P1
WRN	ENST00000521620.5	n.791C>A		non_coding_transcript_exon_variant	7/23	1
WRN	ENST00000650667.1	c.*1772C>A		3_prime_UTR_variant, NMD_transcript_variant	18/34

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000329 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Werner syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 14, 2023

This variant has not been reported in the literature in individuals affected with WRN-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces leucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 720 of the WRN protein (p.Leu720Met). ClinVar contains an entry for this variant (Variation ID: 528169). 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. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.24
BayesDel_addAF	Benign	-0.18	T
BayesDel_noAF	Benign	-0.49
CADD	Benign	12
DANN	Uncertain	0.99
DEOGEN2	Benign	0.21	T
Eigen	Benign	-0.43
Eigen_PC	Benign	-0.60
FATHMM_MKL	Benign	0.23	N
LIST_S2	Uncertain	0.86	D
M_CAP	Benign	0.020	T
MetaRNN	Uncertain	0.51	D
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.6	L
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.41	T
PROVEAN	Benign	-1.9	N
REVEL	Benign	0.11
Sift	Benign	0.045	D
Sift4G	Benign	0.16	T
Polyphen		0.99	D
Vest4		0.49
MVP		0.44
MPC		0.39
ClinPred		0.81	D
GERP RS		1.3
Varity_R		0.22
gMVP		0.55

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: rs920563936; hg19: chr8-30969200;