13-32394815-G-T

Position:

• chr13-32394815-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000059.4(BRCA2):​c.9383G>T​(p.Arg3128Leu) 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 (★). Synonymous variant affecting the same amino acid position (i.e. RP3128R?) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.222

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]

BRCA2 (HGNC:):

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, 0.754

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.9383G>T	p.Arg3128Leu	missense_variant	25/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.9383G>T	p.Arg3128Leu	missense_variant	25/27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.9014G>T	p.Arg3005Leu	missense_variant	25/27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.*1441G>T		non_coding_transcript_exon_variant	24/26	2		ENSP00000506251.1
BRCA2	ENST00000614259.2	n.*1441G>T		3_prime_UTR_variant	24/26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1461788 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727190

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 22, 2023

This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 3128 of the BRCA2 protein (p.Arg3128Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with BRCA2-related conditions. ClinVar contains an entry for this variant (Variation ID: 1012001). 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. 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	0.18
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.010
CADD	Benign	20
DANN	Uncertain	1.0
Eigen	Benign	-0.40
Eigen_PC	Benign	-0.37
FATHMM_MKL	Benign	0.20	N
M_CAP	Uncertain	0.094	D
MetaRNN	Pathogenic	0.75	D;D
MetaSVM	Benign	-0.44	T
PrimateAI	Benign	0.23	T
PROVEAN	Benign	-1.8	N;N
REVEL	Uncertain	0.59
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.011	D;D
Vest4		0.54
MutPred		0.79		Loss of disorder (P = 0.0448);Loss of disorder (P = 0.0448);
MVP		0.88
MPC		0.023
ClinPred		0.92	D
GERP RS		0.40
gMVP		0.62

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: rs397507427; hg19: chr13-32968952;