8-31142701-G-C

Position:

• chr8-31142701-G-C

Variant summary

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

The NM_000553.6(WRN):​c.3309G>C​(p.Lys1103Asn) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000692 in 1,445,864 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: WRN NM_000553.6 missense, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.19

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 (HGNC:):

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	Protein	UniProt
WRN	NM_000553.6	c.3309G>C	p.Lys1103Asn	missense_variant, splice_region_variant	27/35	ENST00000298139.7	NP_000544.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
WRN	ENST00000298139.7	c.3309G>C	p.Lys1103Asn	missense_variant, splice_region_variant	27/35	1	NM_000553.6	ENSP00000298139.5
WRN	ENST00000521620.5	n.1942G>C		splice_region_variant, non_coding_transcript_exon_variant	15/23	1
WRN	ENST00000650667.1	n.*2923G>C		splice_region_variant, non_coding_transcript_exon_variant	26/34			ENSP00000498593.1
WRN	ENST00000650667.1	n.*2923G>C		3_prime_UTR_variant	26/34			ENSP00000498593.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.92e-7 AC: 1 AN: 1445864 Hom.: 0 Cov.: 28 AF XY: 0.00000139 AC XY: 1 AN XY: 718492

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: 9.06e-7

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

Jun 19, 2019

This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with WRN-related disease. This sequence change replaces lysine with asparagine at codon 1103 of the WRN protein (p.Lys1103Asn). The lysine residue is weakly conserved and there is a moderate physicochemical difference between lysine and asparagine. This variant also falls at the last nucleotide of exon 27 of the WRN coding sequence, which is part of the consensus splice site for this exon. 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. Nucleotide substitutions within the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Benign	-0.23	T
BayesDel_noAF	Benign	-0.57
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Benign	0.16	T
Eigen	Benign	-0.066
Eigen_PC	Benign	0.0043
FATHMM_MKL	Uncertain	0.79	D
LIST_S2	Benign	0.56	T
M_CAP	Benign	0.0063	T
MetaRNN	Benign	0.15	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.8	L
PrimateAI	Benign	0.40	T
PROVEAN	Benign	-1.3	N
REVEL	Benign	0.021
Sift	Benign	0.23	T
Sift4G	Benign	0.36	T
Polyphen		0.65	P
Vest4		0.21
MutPred		0.25		Loss of ubiquitination at K1103 (P = 0.0074);
MVP		0.61
MPC		0.27
ClinPred		0.88	D
GERP RS		3.2
Varity_R		0.15
gMVP		0.19

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.95
SpliceAI score (max)		0.93		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.93		Position offset: 0

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

Publications

LitVar

Other links and lift over

dbSNP: rs770117143; hg19: chr8-31000217;