8-31076217-A-G

Position:

• chr8-31076217-A-G

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_000553.6(WRN):​c.769A>G​(p.Ile257Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000684 in 1,461,662 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 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. I257T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: WRN NM_000553.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: -0.284

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 Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.046524912).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
WRN	NM_000553.6	c.769A>G	p.Ile257Val	missense_variant	8/35	ENST00000298139.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
WRN	ENST00000298139.7	c.769A>G	p.Ile257Val	missense_variant	8/35	1	NM_000553.6	P1
WRN	ENST00000651642.1	c.64A>G	p.Ile22Val	missense_variant	2/4
WRN	ENST00000650667.1	c.*383A>G		3_prime_UTR_variant, NMD_transcript_variant	7/34

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461662 Hom.: 0 Cov.: 31 AF XY: 0.00000963 AC XY: 7 AN XY: 727140

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000630

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Asia WGS AF: 0.000289 AC: 1 AN: 3476

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Werner syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 06, 2023

This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 257 of the WRN protein (p.Ile257Val). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with WRN-related conditions. ClinVar contains an entry for this variant (Variation ID: 290683). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The valine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Eurofins Ntd Llc (ga)

Sep 14, 2016

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.078
BayesDel_addAF	Benign	-0.27	T
BayesDel_noAF	Benign	-0.62
CADD	Benign	11
DANN	Benign	0.97
DEOGEN2	Benign	0.067	T
Eigen	Benign	-0.74
Eigen_PC	Benign	-0.69
FATHMM_MKL	Benign	0.093	N
LIST_S2	Benign	0.63	T
M_CAP	Benign	0.0045	T
MetaRNN	Benign	0.047	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.9	L
MutationTaster	Benign	0.93	N
PrimateAI	Benign	0.32	T
PROVEAN	Benign	-0.44	N
REVEL	Benign	0.027
Sift	Benign	0.11	T
Sift4G	Benign	0.24	T
Polyphen		0.016	B
Vest4		0.072
MutPred		0.098		Gain of disorder (P = 0.1313);
MVP		0.51
MPC		0.058
ClinPred		0.047	T
GERP RS		-0.98
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.018
gMVP		0.13

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: rs886044530; hg19: chr8-30933733;