13-32341192-A-T

Position:

• chr13-32341192-A-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_000059.4(BRCA2):​c.6837A>T​(p.Leu2279Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,580 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign 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: 0.0000048 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4 B:1
• Conservation: PhyloP100: 0.832

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 Likely_benign. Variant got -2 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.13368791).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.6837A>T	p.Leu2279Phe	missense_variant	11/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.6837A>T	p.Leu2279Phe	missense_variant	11/27	5	NM_000059.4	ENSP00000369497	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461580 Hom.: 0 Cov.: 35 AF XY: 0.00000825 AC XY: 6 AN XY: 727100

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: 0.00000540

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Apr 19, 2023	The p.L2279F variant (also known as c.6837A>T), located in coding exon 10 of the BRCA2 gene, results from an A to T substitution at nucleotide position 6837. The leucine at codon 2279 is replaced by phenylalanine, an amino acid with highly similar properties. This variant was identified in one individual of West Irish descent who fulfilled diagnostic testing criteria for hereditary breast and ovarian cancer but was classified as a variant of unknown significance (McVeigh TP et al. Ir J Med Sci 2013). This amino acid position is poorly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	May 17, 2023	This missense variant replaces leucine with phenylalanine at codon 2279 of the BRCA2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in individuals with a personal or family history of breast and/or ovarian cancer (PMID: 23884708, 33471991; Leiden Open Variation Database DB-ID BRCA2_008517). This variant has been identified in 1/246020 chromosomes 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. -
Likely benign, criteria provided, single submitter	curation	University of Washington Department of Laboratory Medicine, University of Washington	Mar 23, 2023	Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673). -

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

Uncertain significance, no assertion criteria provided

clinical testing

Sharing Clinical Reports Project (SCRP)

Mar 12, 2012

- -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 25, 2023

This sequence change replaces leucine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 2279 of the BRCA2 protein (p.Leu2279Phe). This variant is present in population databases (rs431825346, gnomAD 0.0009%). This missense change has been observed in individual(s) with breast cancer (PMID: 23884708). This variant is also known as 7065A>T. ClinVar contains an entry for this variant (Variation ID: 96842). 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%. 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	0.075
BayesDel_addAF	Benign	-0.012	T
BayesDel_noAF	Benign	-0.25
CADD	Benign	10
DANN	Benign	0.96
Eigen	Benign	-0.86
Eigen_PC	Benign	-0.83
FATHMM_MKL	Benign	0.24	N
M_CAP	Uncertain	0.23	D
MetaRNN	Benign	0.13	T;T
MetaSVM	Benign	-0.87	T
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.30	T
PROVEAN	Benign	-0.14	N;N
REVEL	Benign	0.18
Sift	Uncertain	0.0010	D;D
Sift4G	Benign	0.086	T;T
Vest4		0.13
MutPred		0.24		Loss of sheet (P = 0.1398);Loss of sheet (P = 0.1398);
MVP		0.90
MPC		0.025
ClinPred		0.19	T
GERP RS		3.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
gMVP		0.052

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: rs431825346; hg19: chr13-32915329;