13-32356517-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PM5 PP3

The NM_000059.4(BRCA2):c.7525A>G(p.Ser2509Gly) 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 pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S2509N) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.40

Genes affected

BRCA2 (HGNC:1101): (BRCA2 DNA repair associated) Inherited mutations in BRCA1 and this gene, BRCA2, confer increased lifetime risk of developing breast or ovarian cancer. Both BRCA1 and BRCA2 are involved in maintenance of genome stability, specifically the homologous recombination pathway for double-strand DNA repair. The largest exon in both genes is exon 11, which harbors the most important and frequent mutations in breast cancer patients. The BRCA2 gene was found on chromosome 13q12.3 in human. The BRCA2 protein contains several copies of a 70 aa motif called the BRC motif, and these motifs mediate binding to the RAD51 recombinase which functions in DNA repair. BRCA2 is considered a tumor suppressor gene, as tumors with BRCA2 mutations generally exhibit loss of heterozygosity (LOH) of the wild-type allele. [provided by RefSeq, May 2020]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 7 benign, 17 uncertain in NM_000059.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr13-32356517-AG-GACT is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2680263.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.804

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA2	NM_000059.4	c.7525A>G	p.Ser2509Gly	missense_variant	15/27	ENST00000380152.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA2	ENST00000380152.8	c.7525A>G	p.Ser2509Gly	missense_variant	15/27	5	NM_000059.4	A2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Nov 15, 2022

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; Also known as 7753A>G; This variant is associated with the following publications: (PMID: 31911673, 12228710) -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 16, 2015

The p.S2509G variant (also known as c.7525A>G), located in coding exon 14 of the BRCA2 gene, results from an A to G substitution at nucleotide position 7525. The serine at codon 2509 is replaced by glycine, an amino acid with similar properties. This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6503 samples (13006 alleles) with coverage at this position. To date, this alteration has been detected with an allele frequency of approximately 0.001% (greater than 150000 alleles tested) in our clinical cohort. This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of p.S2509G remains unclear. -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Apr 24, 2019

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 (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with BRCA2-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces serine with glycine at codon 2509 of the BRCA2 protein (p.Ser2509Gly). The serine residue is highly conserved and there is a small physicochemical difference between serine and glycine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.030
Cadd	Uncertain	25
Dann	Uncertain	1.0
Eigen	Uncertain	0.66
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Uncertain	0.91	D
M_CAP	Uncertain	0.13	D
MetaRNN	Pathogenic	0.80	D;D
MetaSVM	Uncertain	0.52	D
MutationTaster	Benign	0.97	D;D
PrimateAI	Benign	0.35	T
PROVEAN	Benign	-1.1	N;N
REVEL	Uncertain	0.63
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.010	D;D
Vest4		0.52
MutPred		0.80		Gain of catalytic residue at P2505 (P = 0.0741);Gain of catalytic residue at P2505 (P = 0.0741);
MVP		0.96
MPC		0.16
ClinPred		0.96	D
GERP RS		4.2
gMVP		0.55

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.16		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: rs1555286268; hg19: chr13-32930654;