13-32370433-G-C

Variant names:

• chr13-32370433-G-C
• rs80359080
• NM_000059.4:c.8363G>C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP3_Moderate PP5

The NM_000059.4(BRCA2):​c.8363G>C​(p.Trp2788Ser) variant causes a missense change involving the alteration of a 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 Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:3
• Conservation: PhyloP100: 9.94

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 Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.906
• PP5: Variant 13-32370433-G-C is Pathogenic according to our data. Variant chr13-32370433-G-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 52565.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.8363G>C	p.Trp2788Ser	missense_variant	Exon 19 of 27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.8363G>C	p.Trp2788Ser	missense_variant	Exon 19 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.7994G>C	p.Trp2665Ser	missense_variant	Exon 19 of 27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.*421G>C		non_coding_transcript_exon_variant	Exon 18 of 26	2		ENSP00000506251.1
BRCA2	ENST00000614259	n.*421G>C		3_prime_UTR_variant	Exon 18 of 25	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2 Uncertain:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:1 Uncertain:1

Feb 26, 2025

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.W2788S variant (also known as c.8363G>C), located in coding exon 18 of the BRCA2 gene, results from a G to C substitution at nucleotide position 8363. The tryptophan at codon 2788 is replaced by serine, an amino acid with highly dissimilar properties. This alteration, as well as a close match alteration at the same codon (p.W2788R) were found non-functional in a homology-directed DNA repair (HDR) assay (Guidugli L et al. Am. J. Hum. Genet., 2018 02;102:233-248). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Jan 24, 2022

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces tryptophan with serine at codon 2788 of the BRCA2 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). Functional studies have shown that this variant reduces BRCA2 function in homology-mediated repair assays (PMID: 29394989, 33609447). To our knowledge, 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 Pathogenic:1 Uncertain:1

May 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces tryptophan, which is neutral and slightly polar, with serine, which is neutral and polar, at codon 2788 of the BRCA2 protein (p.Trp2788Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with breast cancer (PMID: 36881271). ClinVar contains an entry for this variant (Variation ID: 52565). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (PMID: 33609447) indicates that this missense variant is expected to disrupt BRCA2 function with a positive predictive value of 95%. 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. -

Nov 23, 2018

Cancer Variant Interpretation Group UK, Institute of Cancer Research, London

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: curation

Data used in classification: The frequency of this variant is 0/138,632 individuals (gnomAD) (PM2_mod). This variant is predicted deleterious on AlignGVGD (class: C65), SIFT (Deleterious), Polyphen2 HumVar (probably damaging) and CADD (23.3) (PP3_sup). The variant is in the DNA-binding domain of BRCA2 (PM1_sup). In the VarCall Bayesian statistical model for VUS classification using functional assay data (Guidugli et al Am J Hum Genet 2018; 102:233-248, Couch Lab), the variant has a probability of being deleterious of 0.99 and an overall classification of pathogenic (PS3_strong). Data not used in classification: There are additional reports of this variant in ClinVar (1), BIC (1), and BRCA2 LOVD (1). -

Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:1

Dec 23, 2003

Breast Cancer Information Core (BIC) (BRCA2)

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.70
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.24
CADD	Pathogenic	29
DANN	Uncertain	0.99
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	1.0	D
M_CAP	Pathogenic	0.32	D
MetaRNN	Pathogenic	0.91	D;D
MetaSVM	Uncertain	0.71	D
PrimateAI	Uncertain	0.67	T
PROVEAN	Uncertain	-4.2	D;D
REVEL	Pathogenic	0.74
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Vest4		0.68
MutPred		0.71		Gain of disorder (P = 0);Gain of disorder (P = 0);
MVP		0.96
MPC		0.19
ClinPred		1.0	D
GERP RS		5.2
gMVP		0.92

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs80359080; hg19: chr13-32944570;