rs876658652

Positions:

• chr17-58724037-CA-C

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The ENST00000337432.9(RAD51C):​c.905-2del variant causes a splice acceptor change. The variant allele was found at a frequency of 0.00000657 in 152,102 control chromosomes in the GnomAD database, with no homozygous occurrence. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: RAD51C ENST00000337432.9 splice_acceptor
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 5.10

Genes affected

RAD51C (HGNC:9820): (RAD51 paralog C) This gene is a member of the RAD51 family. RAD51 family members are highly similar to bacterial RecA and Saccharomyces cerevisiae Rad51 and are known to be involved in the homologous recombination and repair of DNA. This protein can interact with other RAD51 paralogs and is reported to be important for Holliday junction resolution. Mutations in this gene are associated with Fanconi anemia-like syndrome. This gene is one of four localized to a region of chromosome 17q23 where amplification occurs frequently in breast tumors. Overexpression of the four genes during amplification has been observed and suggests a possible role in tumor progression. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2013]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-58724037-CA-C is Pathogenic according to our data. Variant chr17-58724037-CA-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 230587.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-58724037-CA-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RAD51C	NM_058216.3	c.905-2del		splice_acceptor_variant		ENST00000337432.9	NP_478123.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RAD51C	ENST00000337432.9	c.905-2del		splice_acceptor_variant		1	NM_058216.3	ENSP00000336701	P2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152102 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 30

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152102 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74298

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:8

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Dec 20, 2023	Canonical splice site variant demonstrated to result in aberrant splicing in a gene for which loss of function is a known mechanism of disease (PMID: 35740625); Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 26824983, 22725699, 26261251, 26720728, 26822949, 29566657, 36974006, 35740625, 37444530, 32107557) -
Likely pathogenic, criteria provided, single submitter	clinical testing	Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital	Aug 15, 2023	- -
Pathogenic, no assertion criteria provided	curation	Leiden Open Variation Database	Feb 28, 2020	Curator: Arleen D. Auerbach. Submitter to LOVD: Christine Rappaport. -
Pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Feb 01, 2023	RAD51C: PVS1, PM2 -

Hereditary cancer-predisposing syndrome Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Apr 15, 2019	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Apr 10, 2023	The c.905-2delA intronic variant, located in intron 6 of the RAD51C gene, results from a deletion of one nucleotide within intron 6 of the RAD51C gene. This variant was detected in 3/6178 families with a history of tubo-ovarian carcinoma or breast cancer. (Yang X et al. J Natl Cancer Inst, 2020 Dec;112:1242-1250). This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice acceptor site. RNA studies have demonstrated that this alteration results in abnormal splicing in the set of samples tested (Ambry internal data). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. As such, this alteration is classified as likely pathogenic. -

Fanconi anemia complementation group O Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 02, 2023

Disruption of this splice site has been observed in individual(s) with hereditary breast and/or ovarian cancer (PMID: 32107557). This sequence change affects a splice site in intron 6 of the RAD51C gene. RNA analysis indicates that disruption of this splice site induces altered splicing and likely disrupts the C-terminus of the protein. This variant is not present in population databases (gnomAD no frequency). ClinVar contains an entry for this variant (Variation ID: 230587). Studies have shown that disruption of this splice site results in exon 7 skipping and introduces a new termination codon (PMID: 35740625; Invitae). However the mRNA is not expected to undergo nonsense-mediated decay. This variant disrupts the nuclear localization signal (NLS) of the RAD51C protein, which is important for proper localization and function of the RAD51C protein (PMID:12966089). While functional studies have not been performed to directly test the effect of this variant on RAD51C protein function, this suggests that disruption of this region of the protein is causative of disease. For these reasons, this variant has been classified as Pathogenic. -

Breast-ovarian cancer, familial, susceptibility to, 3 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Myriad Genetics, Inc.

Jan 03, 2024

This variant is considered likely pathogenic. This variant occurs within a consensus splice junction and is predicted to result in abnormal mRNA splicing of either an out-of-frame exon or an in-frame exon necessary for protein stability and/or normal function. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.91		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.91		Position offset: 3

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

Publications

LitVar

Other links and lift over

dbSNP: rs876658652; hg19: chr17-56801398;