chr13-32370508-G-A

Position:

• chr13-32370508-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 4P and 1B. PM2 PP3_Moderate BP6

The NM_000059.4(BRCA2):​c.8438G>A​(p.Gly2813Glu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,672 control chromosomes in the GnomAD database, with no homozygous occurrence. 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)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4 B:1
• Conservation: PhyloP100: 9.92

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 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.873
• BP6: Variant 13-32370508-G-A is Benign according to our data. Variant chr13-32370508-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 52589.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=2, Likely_benign=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.8438G>A	p.Gly2813Glu	missense_variant	19/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.8438G>A	p.Gly2813Glu	missense_variant	19/27	5	NM_000059.4	ENSP00000369497	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461672 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727154

Gnomad4 AFR exome AF: 0.00

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: 0.00000360

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

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

Uncertain significance, no assertion criteria provided	clinical testing	Breast Cancer Information Core (BIC) (BRCA2)	Jun 12, 2000	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Feb 24, 2017	- -

BRCA2-related cancer predisposition Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Aug 13, 2024

This missense variant replaces glycine with glutamic acid at codon 2813 of the BRCA2 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function. Functional studies have reported that the variant protein does not impact BRCA2 function in homology-directed DNA repair assays (PMID: 23108138, 29394989). 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

Labcorp Genetics (formerly Invitae), Labcorp

Dec 11, 2023

This sequence change replaces glycine, which is neutral and non-polar, with glutamic acid, which is acidic and polar, at codon 2813 of the BRCA2 protein (p.Gly2813Glu). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with glioma (PMID: 26580448). ClinVar contains an entry for this variant (Variation ID: 52589). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (PMID: 33609447) indicates that this missense variant is not expected to disrupt BRCA2 function with a negative predictive value of 95%. Experimental studies have shown that this missense change does not substantially affect BRCA2 function (PMID: 23108138, 29394989). 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. -

Hereditary cancer-predisposing syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 30, 2024

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.80
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	26
DANN	Uncertain	1.0
Eigen	Pathogenic	0.85
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Pathogenic	0.59	D
MetaRNN	Pathogenic	0.87	D;D
MetaSVM	Pathogenic	0.96	D
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.71	T
PROVEAN	Benign	-2.1	N;N
REVEL	Pathogenic	0.82
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Vest4		0.86
MutPred		0.53		Gain of solvent accessibility (P = 0.0171);Gain of solvent accessibility (P = 0.0171);
MVP		0.98
MPC		0.18
ClinPred		1.0	D
GERP RS		5.2
gMVP		0.93

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs80359092; hg19: chr13-32944645; COSMIC: COSV101204518; COSMIC: COSV101204518;