8-31157398-C-T

Variant names:

• chr8-31157398-C-T
• rs368876038
• NM_000553.6:c.3850C>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000553.6(WRN):​c.3850C>T​(p.Leu1284Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000889 in 1,461,820 control chromosomes in the GnomAD database, with no homozygous occurrence. 13/22 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. L1284H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000089 (0 hom.)
• Consequence: WRN NM_000553.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.511
• 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 2 ACMG points.

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

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.3850C>T	p.Leu1284Phe	missense	Exon 33 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.3850C>T	p.Leu1284Phe	missense	Exon 33 of 35	ENSP00000298139.5
	WRN	ENST00000521620.5	TSL:1	n.2483C>T		non_coding_transcript_exon	Exon 21 of 23
	WRN	ENST00000650667.1		n.*3464C>T		non_coding_transcript_exon	Exon 32 of 34	ENSP00000498593.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000889 AC: 13 AN: 1461820 Hom.: 0 Cov.: 31 AF XY: 0.00000688 AC XY: 5 AN XY: 727224

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44716

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53380

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000989 AC: 11 AN: 1111994

Other (OTH) AF: 0.0000331 AC: 2 AN: 60394

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.00000756

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Werner syndrome Uncertain:1

Aug 24, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. ClinVar contains an entry for this variant (Variation ID: 572355). This variant has not been reported in the literature in individuals affected with WRN-related conditions. This variant is present in population databases (rs368876038, gnomAD 0.007%). This sequence change replaces leucine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 1284 of the WRN protein (p.Leu1284Phe). 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	Benign	0.13
BayesDel_addAF	Benign	-0.023	T
BayesDel_noAF	Benign	-0.27
CADD	Benign	21
DANN	Uncertain	1.0
DEOGEN2	Benign	0.11	T
Eigen	Uncertain	0.32
Eigen_PC	Uncertain	0.26
FATHMM_MKL	Benign	0.64	D
LIST_S2	Benign	0.74	T
M_CAP	Benign	0.021	T
MetaRNN	Uncertain	0.52	D
MetaSVM	Uncertain	-0.24	T
MutationAssessor	Uncertain	2.8	M
PhyloP100		0.51
PrimateAI	Benign	0.39	T
PROVEAN	Benign	-2.1	N
REVEL	Benign	0.22
Sift	Benign	0.053	T
Sift4G	Benign	0.10	T
Polyphen		0.98	D
Vest4		0.52
MVP		0.78
MPC		0.37
ClinPred		0.97	D
GERP RS		4.7
Varity_R		0.055
gMVP		0.28
Mutation Taster		=79/21	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs368876038; hg19: chr8-31014914;