13-32363391-C-T

Position:

• chr13-32363391-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_000059.4(BRCA2):​c.8189C>T​(p.Ala2730Val) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,864 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 Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 3.81

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 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.841

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.8189C>T	p.Ala2730Val	missense_variant	18/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.8189C>T	p.Ala2730Val	missense_variant	18/27	5	NM_000059.4	ENSP00000369497	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250670 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135580

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461864 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727226

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Apr 28, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Mar 29, 2023	The p.A2730V variant (also known as c.8189C>T), located in coding exon 17 of the BRCA2 gene, results from a C to T substitution at nucleotide position 8189. The alanine at codon 2730 is replaced by valine, an amino acid with similar properties. This variant had intermediate function in a homology-directed DNA repair (HDR) assay (Hart SN et al. Genet Med, 2019 Jan;21:71-80). This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

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

Uncertain significance, no assertion criteria provided

clinical testing

Breast Cancer Information Core (BIC) (BRCA2)

Oct 29, 2001

- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Aug 25, 2020

The BRCA2 c.8189C>T; p.Ala2730Val variant (rs80359067), to our knowledge, is not reported in the medical literature in association with disease but is reported in ClinVar (Variation ID: 52522). This variant is only observed on one allele in the Genome Aggregation Database, indicating it is not a common polymorphism. The alanine at codon 2730 is highly conserved, and computational analyses (SIFT: tolerated, PolyPhen-2: damaging) predict conflicting effects of this variant on protein structure/function. Due to limited information, the clinical significance of the p.Ala2730Val variant is uncertain at this time. -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 05, 2023

This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 2730 of the BRCA2 protein (p.Ala2730Val). This variant is present in population databases (rs80359067, gnomAD 0.003%). This missense change has been observed in individual(s) with clinical features of BRCA2-related conditions (PMID: 10923033). ClinVar contains an entry for this variant (Variation ID: 52522). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt BRCA2 protein function with a negative predictive value of 95%. Experimental studies are conflicting or provide insufficient evidence to determine the effect of this variant on BRCA2 function (PMID: 29394989). This variant disrupts the p.Ala2730 amino acid residue in BRCA2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 25186627, 28888541, 31853058, 32886903, 33609447; Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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	Benign	0.28
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Pathogenic	0.20
CADD	Benign	23
DANN	Uncertain	1.0
Eigen	Uncertain	0.52
Eigen_PC	Uncertain	0.49
FATHMM_MKL	Uncertain	0.96	D
M_CAP	Uncertain	0.10	D
MetaRNN	Pathogenic	0.84	D;D
MetaSVM	Uncertain	0.25	D
MutationTaster	Benign	0.97	D;D
PrimateAI	Benign	0.44	T
PROVEAN	Benign	-1.2	N;N
REVEL	Uncertain	0.61
Sift	Benign	0.094	T;T
Sift4G	Benign	0.16	T;T
Vest4		0.56
MutPred		0.63		Gain of methylation at K2729 (P = 0.0378);Gain of methylation at K2729 (P = 0.0378);
MVP		0.93
MPC		0.14
ClinPred		0.93	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
gMVP		0.78

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs80359067; hg19: chr13-32937528;