rs959089047

Positions:

• chr13-32340255-A-G
• chr13-32340255-A-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.5900A>G​(p.Lys1967Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,730 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K1967M) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7 B:1
• Conservation: PhyloP100: -0.0240

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=0.105636925).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA2	NM_000059.4	c.5900A>G	p.Lys1967Arg	missense_variant	11/27	ENST00000380152.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA2	ENST00000380152.8	c.5900A>G	p.Lys1967Arg	missense_variant	11/27	5	NM_000059.4	A2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461730 Hom.: 0 Cov.: 46 AF XY: 0.00 AC XY: 0 AN XY: 727162

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000282 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:3 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Sep 11, 2023	The p.K1967R variant (also known as c.5900A>G), located in coding exon 10 of the BRCA2 gene, results from an A to G substitution at nucleotide position 5900. The lysine at codon 1967 is replaced by arginine, an amino acid with highly similar properties. This variant was reported in 0/60,466 breast cancer cases and in 1/53,461 controls (Dorling et al. N Engl J Med. 2021 02;384:428-439). 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. 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	Jun 14, 2022	This missense variant replaces lysine with arginine at codon 1967 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 an individual affected with ovarian cancer and in one unaffected individual (PMID: 33273034, 33471991; Leiden Open Variation Database DB-ID BRCA2_002903). 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. -
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). -
Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Jul 02, 2021	- -

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

Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Jan 11, 2024	This missense variant replaces lysine with arginine at codon 1967 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 an individual affected with ovarian cancer and in one unaffected individual (PMID: 33273034, 33471991; Leiden Open Variation Database DB-ID BRCA2_002903). 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. -
Uncertain significance, no assertion criteria provided	clinical testing	BRCAlab, Lund University	Mar 02, 2020	- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Aug 24, 2018

This variant is denoted BRCA2 c.5900A>G at the cDNA level, p.Lys1967Arg (K1967R) at the protein level, and results in the change of a Lysine to an Arginine (AAG>AGG). Using alternate nomenclature, this variant would be defined as BRCA2 6128A>G. This variant has not, to our knowledge, been published in the literature as a pathogenic or benign germline variant. BRCA2 Lys1967Arg was not observed in large population cohorts (Lek 2016). This variant is located in the RAD51 Binding Domain (Roy 2012). While protein-based in silico analysis supports that this variant does not alter protein structure/function, splicing models predict the creation of a new splice site. However, in the absence of RNA or functional studies, the actual effect of this variant is unknown. Based on currently available evidence, it is unclear whether BRCA2 Lys1967Arg is a pathogenic or benign variant. We consider it to be a variant of uncertain significance. -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jan 04, 2024

This sequence change replaces lysine, which is basic and polar, with arginine, which is basic and polar, at codon 1967 of the BRCA2 protein (p.Lys1967Arg). 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: 418085). 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	0.080
BayesDel_addAF	Benign	-0.19	T
BayesDel_noAF	Benign	-0.51
CADD	Benign	3.5
DANN	Benign	0.96
Eigen	Benign	-1.0
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.12	N
M_CAP	Benign	0.044	D
MetaRNN	Benign	0.11	T;T
MetaSVM	Benign	-0.93	T
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.22	T
PROVEAN	Benign	-1.9	N;N
REVEL	Benign	0.10
Sift	Benign	0.082	T;T
Sift4G	Benign	0.64	T;T
Vest4		0.15
MutPred		0.22		Loss of ubiquitination at K1967 (P = 0.0546);Loss of ubiquitination at K1967 (P = 0.0546);
MVP		0.79
MPC		0.020
ClinPred		0.085	T
GERP RS		-3.4
gMVP		0.13

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: rs959089047; hg19: chr13-32914392;