17-58703195-G-C

Position:

• chr17-58703195-G-C

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1_Strong PM2 PP3_Strong PP5_Very_Strong

The NM_058216.3(RAD51C):​c.572-1G>C variant causes a splice acceptor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,459,254 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: RAD51C NM_058216.3 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 7.98

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, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.11759505 fraction of the gene. Cryptic splice site detected, with MaxEntScore 6.4, offset of -33, new splice context is: ttgccaatacatccaaacAGgta. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 17-58703195-G-C is Pathogenic according to our data. Variant chr17-58703195-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 480497.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RAD51C	NM_058216.3	c.572-1G>C		splice_acceptor_variant		ENST00000337432.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RAD51C	ENST00000337432.9	c.572-1G>C		splice_acceptor_variant		1	NM_058216.3	P2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1459254 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726170

Gnomad4 AFR exome AF: 0.0000299

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:8

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 3 Pathogenic:4

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. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Feb 22, 2023	- -
Pathogenic, criteria provided, single submitter	research	Centre for Mendelian Genomics, University Medical Centre Ljubljana	Dec 09, 2022	PVS1_STR, PS4_SUP, PM2_SUP -
Pathogenic, criteria provided, single submitter	clinical testing	Department of Molecular Diagnostics, Institute of Oncology Ljubljana	Oct 24, 2018	- -

Hereditary cancer-predisposing syndrome Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 15, 2023	This variant causes a G>C nucleotide substitution at the -1 position of intron 3 of the RAD51C gene. Splice site prediction tools predict that this variant may have a significant impact on RNA splicing. A minigene splicing assay has shown that this variant resulted in the out-of-frame skipping of exon 4 (PMID: 35740625). This variant has been reported in an individual affected with ovarian cancer (PMID: 26261251). Different substitutions in canonical splice site positions at this acceptor site, c.572-1G>T and c.572-2A>G, have been reported in one individual each affected with breast cancer or ovarian cancer (PMID: 27908594, 30949688). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Loss of RAD51C function is a known mechanism of disease. Based on the available evidence, this variant is classified as Likely Pathogenic. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Aug 31, 2023	The c.572-1G>C intronic variant results from a G to C substitution one nucleotide before coding exon 4 of the RAD51C gene. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). 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; however, direct evidence is insufficient at this time (Ambry internal data). 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:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Invitae	Dec 17, 2023	This sequence change affects an acceptor splice site in intron 3 of the RAD51C gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in RAD51C are known to be pathogenic (PMID: 20400964, 21990120, 24800917, 29278735). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individual(s) with breast or ovarian cancer (PMID: 26261251, 28888541, 32107557). ClinVar contains an entry for this variant (Variation ID: 480497). Studies have shown that disruption of this splice site is associated with inconclusive levels of altered splicing (Invitae). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Centre for Mendelian Genomics, University Medical Centre Ljubljana	Feb 20, 2019	This variant was classified as: Pathogenic. The following ACMG criteria were applied in classifying this variant: PVS1,PM2,PP5. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.19
CADD	Pathogenic	28
DANN	Uncertain	0.99
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Uncertain	0.92	D
MutationTaster	Benign	1.0	D;D
GERP RS		5.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.99		Position offset: 1

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

Publications

LitVar

Other links and lift over

dbSNP: rs1413872299; hg19: chr17-56780556;