13-32376683-A-T

Variant names:

• chr13-32376683-A-T
• rs864622658
• NM_000059.4:c.8646A>T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_000059.4(BRCA2):​c.8646A>T​(p.Lys2882Asn) 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 benign outcome for this variant. 13/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.562

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 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.21105164).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.8646A>T	p.Lys2882Asn	missense_variant	Exon 21 of 27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.8646A>T	p.Lys2882Asn	missense_variant	Exon 21 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.8277A>T	p.Lys2759Asn	missense_variant	Exon 21 of 27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.*704A>T		non_coding_transcript_exon_variant	Exon 20 of 26	2		ENSP00000506251.1
BRCA2	ENST00000614259	n.*704A>T		3_prime_UTR_variant	Exon 20 of 25	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

May 24, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.K2882N variant (also known as c.8646A>T), located in coding exon 20 of the BRCA2 gene, results from an A to T substitution at nucleotide position 8646. The lysine at codon 2882 is replaced by asparagine, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Hereditary breast ovarian cancer syndrome Uncertain:1

May 20, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 tolerated, 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. ClinVar contains an entry for this variant (Variation ID: 220790). This variant is not present in population databases (ExAC no frequency). This sequence change replaces lysine with asparagine at codon 2882 of the BRCA2 protein (p.Lys2882Asn). The lysine residue is weakly conserved and there is a moderate physicochemical difference between lysine and asparagine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.16
BayesDel_addAF	Benign	-0.048	T
BayesDel_noAF	Benign	-0.31
CADD	Benign	16
DANN	Uncertain	0.99
Eigen	Benign	-0.57
Eigen_PC	Benign	-0.77
FATHMM_MKL	Benign	0.25	N
M_CAP	Uncertain	0.15	D
MetaRNN	Benign	0.21	T;T
MetaSVM	Benign	-0.76	T
PrimateAI	Benign	0.28	T
PROVEAN	Benign	-0.88	N;N
REVEL	Benign	0.23
Sift	Uncertain	0.0050	D;D
Sift4G	Uncertain	0.037	D;D
Vest4		0.29
MutPred		0.24		Loss of ubiquitination at K2882 (P = 8e-04);Loss of ubiquitination at K2882 (P = 8e-04);
MVP		0.83
MPC		0.031
ClinPred		0.69	D
GERP RS		-3.4
gMVP		0.21

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: rs864622658; hg19: chr13-32950820;