13-32337895-G-C

Position:

chr13-32337895-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

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. 11/19 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. K1180R) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

BRCA2
NM_000059.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1

Conservation

PhyloP100: 0.195

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.2886908).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4 linkuse as main transcript	c.3540G>C	p.Lys1180Asn	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 linkuse as main transcript	c.3540G>C	p.Lys1180Asn	missense_variant	11/27	5	NM_000059.4	ENSP00000369497	A2

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000399

AC:

AN:

250916

Hom.:

AF XY:

0.00000737

AC XY:

AN XY:

135600

show subpopulations

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000205

AC:

AN:

1461776

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727176

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000504

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

Cov.:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome

Uncertain:2Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Apr 14, 2019	- -
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	clinical testing	Ambry Genetics	Oct 03, 2023	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. -

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Dec 29, 2022	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) -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jun 18, 2023	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

Uncertain significance, criteria provided, single submitter

clinical testing

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

May 05, 2023

- -

Familial cancer of breast

Uncertain:1

Uncertain significance, no assertion criteria provided

curation

Center for Precision Medicine, Meizhou People's Hospital

- -

Hereditary breast ovarian cancer syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 27, 2023

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. 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. ClinVar contains an entry for this variant (Variation ID: 220061). This missense change has been observed in individual(s) with breast cancer and/or ovarian cancer (PMID: 30093976, 32101877). This variant is present in population databases (no rsID available, gnomAD 0.006%). 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). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.26

BayesDel_addAF

Benign

-0.23

BayesDel_noAF

Benign

-0.41

CADD

Benign

DANN

Uncertain

1.0

Eigen

Benign

-0.66

Eigen_PC

Benign

-0.72

FATHMM_MKL

Benign

0.13

M_CAP

Uncertain

0.12

MetaRNN

Benign

0.29

T;T

MetaSVM

Benign

-0.91

MutationTaster

Benign

1.0

N;N

PrimateAI

Benign

0.29

PROVEAN

Uncertain

-4.0

D;D

REVEL

Benign

0.16

Sift

Uncertain

0.022

D;D

Sift4G

Benign

0.26

T;T

Vest4

0.48

MutPred

0.29

Loss of ubiquitination at K1180 (P = 0.0098);Loss of ubiquitination at K1180 (P = 0.0098);

MVP

0.80

MPC

0.059

ClinPred

0.53

GERP RS

0.85

gMVP

0.31

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over