8-31100849-G-T

Variant names:

• chr8-31100849-G-T
• rs755426500
• NM_000553.6:c.1982G>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.1982G>T​(p.Gly661Val) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,460,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G661A) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: WRN NM_000553.6 missense, splice_region
• Scores: Splicing: ADA: 0.9993
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.68
• Publications: 2 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: Ambry Genetics, G2P, Orphanet, ClinGen, Labcorp Genetics (formerly Invitae)
• 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: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	WRN	NM_000553.6	MANE Select	c.1982G>T	p.Gly661Val	missense splice_region	Exon 18 of 35	NP_000544.2	Q14191

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	WRN	ENST00000298139.7	TSL:1 MANE Select	c.1982G>T	p.Gly661Val	missense splice_region	Exon 18 of 35	ENSP00000298139.5	Q14191
	WRN	ENST00000521620.5	TSL:1	n.615G>T		splice_region non_coding_transcript_exon	Exon 6 of 23
	WRN	ENST00000966176.1		c.1982G>T	p.Gly661Val	missense splice_region	Exon 18 of 35	ENSP00000636235.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251294 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460880 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 726766

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33446

American (AMR) AF: 0.00 AC: 0 AN: 44702

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26122

East Asian (EAS) AF: 0.00 AC: 0 AN: 39670

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86214

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53342

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5752

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1111272

Other (OTH) AF: 0.00 AC: 0 AN: 60360

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.79
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	0.040
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Benign	0.29	T
Eigen	Pathogenic	0.75
Eigen_PC	Pathogenic	0.71
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.86	D
M_CAP	Benign	0.019	T
MetaRNN	Pathogenic	0.86	D
MetaSVM	Benign	-1.2	T
MutationAssessor	Benign	1.5	L
PhyloP100		7.7
PrimateAI	Uncertain	0.62	T
PROVEAN	Pathogenic	-6.8	D
REVEL	Uncertain	0.46
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.0040	D
Polyphen		1.0	D
Vest4		0.82
MutPred		0.49		Loss of catalytic residue at D659 (P = 0.2849)
MVP		0.82
MPC		0.43
ClinPred		0.98	D
GERP RS		5.7
Varity_R		0.98
gMVP		0.83
Mutation Taster		=33/67	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.77
SpliceAI score (max)		0.36		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.36		Position offset: 0

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs755426500; hg19: chr8-30958365;