rs1554530875

Positions:

• chr8-31132386-G-A

Variant summary

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

The NM_000553.6(WRN):​c.2847G>A​(p.Met949Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,772 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/23 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: WRN NM_000553.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.152

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=0.037634224).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
WRN	NM_000553.6	c.2847G>A	p.Met949Ile	missense_variant	24/35	ENST00000298139.7	NP_000544.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
WRN	ENST00000298139.7	c.2847G>A	p.Met949Ile	missense_variant	24/35	1	NM_000553.6	ENSP00000298139	P1
WRN	ENST00000521620.5	n.1480G>A		non_coding_transcript_exon_variant	12/23	1
WRN	ENST00000650667.1	c.*2461G>A		3_prime_UTR_variant, NMD_transcript_variant	23/34			ENSP00000498593

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461772 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727176

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

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

Feb 03, 2017

This sequence change replaces methionine with isoleucine at codon 949 of the WRN protein (p.Met949Ile). The methionine residue is weakly conserved and there is a small physicochemical difference between methionine and isoleucine. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a WRN-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: (SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). The isoleucine amino acid residue is found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may alter RNA splicing, but this prediction has not been confirmed by published transcriptional studies. In summary, this variant is a novel missense change with uncertain impact on mRNA splicing and protein function. It has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Benign	-0.36	T
BayesDel_noAF	Benign	-0.75
CADD	Benign	8.4
DANN	Benign	0.53
DEOGEN2	Benign	0.040	T
Eigen	Benign	-1.6
Eigen_PC	Benign	-1.5
FATHMM_MKL	Benign	0.043	N
LIST_S2	Benign	0.46	T
M_CAP	Benign	0.0033	T
MetaRNN	Benign	0.038	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-2.4	N
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.28	T
PROVEAN	Benign	0.30	N
REVEL	Benign	0.055
Sift	Benign	0.34	T
Sift4G	Benign	0.23	T
Polyphen		0.0	B
Vest4		0.055
MutPred		0.29		Loss of disorder (P = 0.0744);
MVP		0.18
MPC		0.070
ClinPred		0.17	T
GERP RS		0.45
Varity_R		0.046
gMVP		0.24

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.20		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.20		Position offset: 2

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

Publications

LitVar

Other links and lift over

dbSNP: rs1554530875; hg19: chr8-30989902;