13-32337895-G-C

Variant names:

• chr13-32337895-G-C
• rs864622363
• NM_000059.4:c.3540G>C

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP4

The NM_000059.4(BRCA2):​c.3540G>C​(p.Lys1180Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,776 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely benign in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K1180E) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:8 B:2
• Conservation: PhyloP100: 0.195
• Publications: 8 publications found

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 Gene-Disease associations (from GenCC):

• breast-ovarian cancer, familial, susceptibility to, 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), ClinGen
• Fanconi anemia complementation group D1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, ClinGen, G2P
• pancreatic cancer, susceptibility to, 2

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• sarcoma

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• hereditary breast ovarian cancer syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Fanconi anemia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• medulloblastoma

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.2886908).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000059.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BRCA2	NM_000059.4	MANE Select	c.3540G>C	p.Lys1180Asn	missense	Exon 11 of 27	NP_000050.3
	BRCA2	NM_001432077.1		c.3540G>C	p.Lys1180Asn	missense	Exon 11 of 27	NP_001419006.1
	BRCA2	NM_001406720.1		c.3540G>C	p.Lys1180Asn	missense	Exon 11 of 27	NP_001393649.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BRCA2	ENST00000380152.8	TSL:5 MANE Select	c.3540G>C	p.Lys1180Asn	missense	Exon 11 of 27	ENSP00000369497.3
	BRCA2	ENST00000544455.6	TSL:1	c.3540G>C	p.Lys1180Asn	missense	Exon 11 of 27	ENSP00000439902.1
	BRCA2	ENST00000530893.7	TSL:1	c.3171G>C	p.Lys1057Asn	missense	Exon 11 of 27	ENSP00000499438.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000399 AC: 1 AN: 250916 AF XY: 0.00000737

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461776 Hom.: 0 Cov.: 35 AF XY: 0.00000413 AC XY: 3 AN XY: 727176

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.0000504 AC: 2 AN: 39688

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53402

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111948

Other (OTH) AF: 0.0000166 AC: 1 AN: 60392

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:8 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2 Benign:1

Oct 03, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.K1180N variant (also known as c.3540G>C), located in coding exon 10 of the BRCA2 gene, results from a G to C substitution at nucleotide position 3540. The lysine at codon 1180 is replaced by asparagine, an amino acid with similar properties. This alteration has been reported as a variant of unknown significance in an individual with a personal history of ovarian cancer from a cohort of 1191 cancer index patients who underwent clinical evaluation and testing with multigene panels (Chan GHJ et al. Oncotarget, 2018 Jul;9:30649-30660). In another study, this alteration was detected in a patient diagnosed with breast cancer at age 51 (Wu H et al. Hum Hered, 2019 Feb;84:160-169). 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.

Apr 14, 2019

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Mar 23, 2023

University of Washington Department of Laboratory Medicine, University of Washington

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: curation

Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673).

not provided Uncertain:2

Dec 29, 2022

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Observed in individuals with breast or ovarian cancer (Chan et al., 2018; Wu et al., 2019); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Not observed at significant frequency in large population cohorts (gnomAD); Also known as 3768G>C; This variant is associated with the following publications: (PMID: 32101877, 30093976, 29884841, 32377563)

Jun 18, 2023

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In the published literature, this variant has been reported in individuals with breast cancer (PMID: 32101877 (2019), 35918668 (2022)) and ovarian cancer (PMID: 30093976 (2018)). In a large-scale breast cancer association study, the variant was observed in an individual with breast cancer as well as in an unaffected individual (PMID: 33471991 (2021)). The frequency of this variant in the general population, 0.000004 (1/250916 chromosomes (Genome Aggregation Database, http://gnomad.broadinstitute.org)), is uninformative in the assessment of its pathogenicity. Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is benign. Based on the available information, we are unable to determine the clinical significance of this variant.

Breast and/or ovarian cancer Uncertain:1

May 05, 2023

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Familial cancer of breast Uncertain:1

Center for Precision Medicine, Meizhou People's Hospital

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: curation

Hereditary breast ovarian cancer syndrome Uncertain:1

Jan 17, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces lysine, which is basic and polar, with asparagine, which is neutral and polar, at codon 1180 of the BRCA2 protein (p.Lys1180Asn). This variant is present in population databases (no rsID available, gnomAD 0.006%). This missense change has been observed in individual(s) with ovarian and/or breast cancer (PMID: 30093976, 32101877, 35918668). ClinVar contains an entry for this variant (Variation ID: 220061). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) 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.

Familial cancer of breast;C2675520:Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:1

Jul 12, 2021

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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

Mar 04, 2024

Molecular Pathology, Peter Maccallum Cancer Centre

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.26
BayesDel_addAF	Benign	-0.23	T
BayesDel_noAF	Benign	-0.41
CADD	Benign	15
DANN	Uncertain	1.0
Eigen	Benign	-0.66
Eigen_PC	Benign	-0.72
FATHMM_MKL	Benign	0.13	N
M_CAP	Uncertain	0.12	D
MetaRNN	Benign	0.29	T
MetaSVM	Benign	-0.91	T
PhyloP100		0.20
PrimateAI	Benign	0.29	T
PROVEAN	Uncertain	-4.0	D
REVEL	Benign	0.16
Sift	Uncertain	0.022	D
Sift4G	Benign	0.26	T
Vest4		0.48
MutPred		0.29		Loss of ubiquitination at K1180 (P = 0.0098)
MVP		0.80
MPC		0.059
ClinPred		0.53	D
GERP RS		0.85
gMVP		0.31
Mutation Taster		=71/29	polymorphism

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

Other links and lift over

dbSNP: rs864622363; hg19: chr13-32912032; COSMIC: COSV99061700;