chr17-58720812-G-A

Position:

• chr17-58720812-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_058216.3(RAD51C):​c.904G>A​(p.Gly302Arg) variant causes a missense, splice region change. The variant was absent in control chromosomes in GnomAD project. 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 Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in same amino acid change has been previously reported as Uncertain significancein ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G302V) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: RAD51C NM_058216.3 missense, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:3
• Conservation: PhyloP100: 5.24

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 Likely_pathogenic. Variant got 6 ACMG points.

• 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.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RAD51C	NM_058216.3	c.904G>A	p.Gly302Arg	missense_variant, splice_region_variant	6/9	ENST00000337432.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RAD51C	ENST00000337432.9	c.904G>A	p.Gly302Arg	missense_variant, splice_region_variant	6/9	1	NM_058216.3	P2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 31

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:1 Uncertain:1

Likely pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Aug 02, 2023	The c.904G>A variant (also known as p.G302R), located in coding exon 6 of the RAD51C gene, results from a G to A substitution at nucleotide position 904. The amino acid change results in glycine to arginine at codon 302, an amino acid with dissimilar properties. However, this change occurs in the last base pair of coding exon 6, which makes it likely to have some effect on normal mRNA splicing. This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice donor site and may result in the creation or strengthening of a novel splice donor site. RNA studies have demonstrated that this alteration results in abnormal splicing in the set of samples tested (Ambry internal data). Based on the majority of available evidence to date, this variant is likely to be pathogenic. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 18, 2021	This variant causes a G to A nucleotide substitution at the last nucleotide of exon 6 of the RAD51C gene and replaces glycine with arginine at codon 302 of the RAD51C protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). Splice site prediction tools suggest that this variant may have a significant impact on RNA splicing, although this prediction has not been confirmed in published RNA studies. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Mendelics

Jul 02, 2018

- -

Fanconi anemia complementation group O Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 06, 2023

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 302 of the RAD51C protein (p.Gly302Arg). RNA analysis indicates that this missense change induces altered splicing and may result in an absent or disrupted protein product. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with RAD51C-related conditions. ClinVar contains an entry for this variant (Variation ID: 478781). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Studies have shown that this missense change results in skipping of exon 7 and introduces a premature termination codon (Invitae). The resulting mRNA is expected to undergo nonsense-mediated decay. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.29
CADD	Pathogenic	35
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.32	T;D
Eigen	Pathogenic	0.90
Eigen_PC	Pathogenic	0.81
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.96	D;D
M_CAP	Uncertain	0.14	D
MetaRNN	Pathogenic	0.98	D;D
MetaSVM	Uncertain	0.46	D
MutationAssessor	Pathogenic	4.3	.;H
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-6.7	.;D
REVEL	Pathogenic	0.70
Sift	Uncertain	0.0010	.;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	.;D
Vest4		0.94
MutPred		0.96		Gain of MoRF binding (P = 0.0373);Gain of MoRF binding (P = 0.0373);
MVP		0.93
MPC		0.93
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.93
gMVP		0.94

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.62		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.36		Position offset: 4
DS_DL_spliceai		0.62		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: rs1555602158; hg19: chr17-56798173;