chr7-152648694-CTG-C

Position:

• chr7-152648694-CTG-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_005431.2(XRCC2):​c.789_790del​(p.Asn263LysfsTer15) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: XRCC2 NM_005431.2 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.15

Genes affected

XRCC2 (HGNC:12829): (X-ray repair cross complementing 2) This gene encodes a member of the RecA/Rad51-related protein family that participates in homologous recombination to maintain chromosome stability and repair DNA damage. This gene is involved in the repair of DNA double-strand breaks by homologous recombination and it functionally complements Chinese hamster irs1, a repair-deficient mutant that exhibits hypersensitivity to a number of different DNA-damaging agents. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0641 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
XRCC2	NM_005431.2	c.789_790del	p.Asn263LysfsTer15	frameshift_variant	3/3	ENST00000359321.2	NP_005422.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
XRCC2	ENST00000359321.2	c.789_790del	p.Asn263LysfsTer15	frameshift_variant	3/3	1	NM_005431.2	ENSP00000352271	P1
XRCC2	ENST00000495707.1	n.811_812del		non_coding_transcript_exon_variant	3/3	1
XRCC2	ENST00000698506.1	c.621_622del	p.Asn207LysfsTer15	frameshift_variant	2/2			ENSP00000513758

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 03, 2016

Experimental studies have not been reported for this variant and it is currently unknown if the last 18 amino acids of the XRCC2 protein are critical for its function. This sequence change deletes 2 nucleotides from exon 3 of the XRCC2 mRNA (c.789_790delCA), causing a frameshift at codon 263. This creates a premature translational stop signal in the last exon of the XRCC2 mRNA (p.Asn263Lysfs*15). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 18 amino acids of the XRCC2 protein. The current clinical and genetic evidence is not sufficient to establish whether loss-of-function variants in XRCC2 cause disease. Therefore, this variant has been classified as a Variant of Uncertain Significance. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a XRCC2-related disease. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.10		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: rs1060502667; hg19: chr7-152345779;