chr8-31120299-A-C

Position:

• chr8-31120299-A-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_000553.6(WRN):​c.2505A>C​(p.Gln835His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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 (★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: WRN NM_000553.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.52

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 Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.38847518).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
WRN	NM_000553.6	c.2505A>C	p.Gln835His	missense_variant	21/35	ENST00000298139.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
WRN	ENST00000298139.7	c.2505A>C	p.Gln835His	missense_variant	21/35	1	NM_000553.6	P1
WRN	ENST00000521620.5	n.1138A>C		non_coding_transcript_exon_variant	9/23	1
WRN	ENST00000520169.1	n.344A>C		non_coding_transcript_exon_variant	1/3	3
WRN	ENST00000650667.1	c.*2119A>C		3_prime_UTR_variant, NMD_transcript_variant	20/34

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

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

Dec 21, 2017

This sequence change replaces glutamine with histidine at codon 835 of the WRN protein (p.Gln835His). The glutamine residue is weakly conserved and there is a small physicochemical difference between glutamine and histidine. 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. 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"). This variant has not been reported in the literature in individuals with WRN-related disease. This variant is not present in population databases (ExAC no frequency). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.16
BayesDel_addAF	Benign	-0.099	T
BayesDel_noAF	Benign	-0.38
CADD	Benign	21
DANN	Uncertain	0.99
DEOGEN2	Benign	0.36	T
Eigen	Benign	-0.14
Eigen_PC	Benign	-0.032
FATHMM_MKL	Uncertain	0.81	D
LIST_S2	Uncertain	0.87	D
M_CAP	Benign	0.037	D
MetaRNN	Benign	0.39	T
MetaSVM	Benign	-0.85	T
MutationAssessor	Benign	-0.47	N
MutationTaster	Benign	0.98	N
PrimateAI	Benign	0.23	T
PROVEAN	Benign	-1.8	N
REVEL	Benign	0.25
Sift	Benign	0.075	T
Sift4G	Benign	0.46	T
Polyphen		0.94	P
Vest4		0.14
MutPred		0.59		Gain of ubiquitination at K830 (P = 0.1162);
MVP		0.70
MPC		0.27
ClinPred		0.85	D
GERP RS		2.1
Varity_R		0.10
gMVP		0.50

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: rs1554528366; hg19: chr8-30977815;