chr13-32338833-A-G

Position:

chr13-32338833-A-G

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 2P and 3B. PM2BP4_ModerateBP6

The NM_000059.4(BRCA2):c.4478A>G(p.Glu1493Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,788 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/19 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: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

BRCA2
NM_000059.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:9B:2

Conservation

PhyloP100: 1.66

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 Likely_benign. Variant got -1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.20477825).

BP6

Variant 13-32338833-A-G is Benign according to our data. Variant chr13-32338833-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 126045.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Benign=1, Uncertain_significance=7}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4 linkuse as main transcript	c.4478A>G	p.Glu1493Gly	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.4478A>G	p.Glu1493Gly	missense_variant	11/27	5	NM_000059.4	ENSP00000369497	A2

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152240

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000399

AC:

AN:

250396

Hom.:

AF XY:

0.00000738

AC XY:

AN XY:

135562

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461548

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727076

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152240

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74384

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000378

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:9Benign:2

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome

Uncertain:2Benign:1

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 04, 2022	The p.E1493G variant (also known as c.4478A>G), located in coding exon 10 of the BRCA2 gene, results from an A to G substitution at nucleotide position 4478. The glutamic acid at codon 1493 is replaced by glycine, an amino acid with similar properties. 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	Apr 08, 2019	- -

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jul 28, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Sep 08, 2017	This variant is denoted BRCA2 c.4478A>G at the cDNA level, p.Glu1493Gly (E1493G) at the protein level, and results in the change of a Glutamic Acid to a Glycine (GAA>GGA). Using alternate nomenclature, this variant would be defined as BRCA2 4706A>G. This variant has not, to our knowledge, been published in the literature as pathogenic or benign. BRCA2 Glu1493Gly was not observed at a significant allele frequency in large population cohorts (NHLBI Exome Sequencing Project, The 1000 Genomes Consortium 2015, Lek 2016). Since Glutamic Acid and Glycine differ in polarity, charge, size or other properties, this is considered a non-conservative amino acid substitution. BRCA2 Glu1493Gly occurs at a position that is not conserved and is located in the RAD51 and POLH binding domains (Roy 2012, Buisson 2014). In silico analyses are inconsistent regarding the effect this variant may have on protein structure and function. Based on currently available evidence, it is unclear whether BRCA2 Glu1493Gly is a pathogenic or benign variant. We consider it to be a variant of uncertain significance. -

Breast-ovarian cancer, familial, susceptibility to, 2

Uncertain:1Benign:1

Benign, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Jul 13, 2023	This variant is considered benign. This variant is strongly associated with less severe personal and family histories of cancer, typical for individuals without pathogenic variants in this gene [PMID: 25085752]. This variant has been observed in trans with a known pathogenic variant in one or more individuals lacking clinical features consistent with gene-specific recessive disease. -
Uncertain significance, no assertion criteria provided	clinical testing	Breast Cancer Information Core (BIC) (BRCA2)	May 29, 2002	- -

Medulloblastoma;C0346153:Familial cancer of breast;C0376358:Malignant tumor of prostate;C1838457:Fanconi anemia complementation group D1;C2675520:Breast-ovarian cancer, familial, susceptibility to, 2;C2751641:Glioma susceptibility 3;C3150546:Pancreatic cancer, susceptibility to, 2;CN033288:Wilms tumor 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 31, 2018

- -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Aug 02, 2021

Variant summary: BRCA2 c.4478A>G (p.Glu1493Gly) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 5.6e-06 in 357318 control chromosomes (gnomAD and publication). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.4478A>G in individuals affected with Hereditary Breast And Ovarian Cancer Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. Six ClinVar submitters (evaluation after 2014) cite the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

BRCA2-related disorder

Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

May 23, 2024

The BRCA2 c.4478A>G variant is predicted to result in the amino acid substitution p.Glu1493Gly. This variant was reported in a control and not in affected individuals in a breast cancer case-control study (Breast Cancer Association Consortium. 2021. PubMed ID: 33471991). This variant is reported in 0.0040% of alleles in individuals of African descent in gnomAD and has conflicting interpretations of pathogenicity in ClinVar ranging from uncertain to benign (http://www.ncbi.nlm.nih.gov/clinvar/variation/126045). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Hereditary breast ovarian cancer syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 18, 2023

This sequence change replaces glutamic acid, which is acidic and polar, with glycine, which is neutral and non-polar, at codon 1493 of the BRCA2 protein (p.Glu1493Gly). This variant is present in population databases (rs80358679, gnomAD 0.004%). 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: 126045). 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

0.077

BayesDel_addAF

Benign

-0.21

BayesDel_noAF

Benign

-0.43

CADD

Benign

DANN

Uncertain

1.0

Eigen

Benign

-0.54

Eigen_PC

Benign

-0.51

FATHMM_MKL

Uncertain

0.88

M_CAP

Benign

0.041

MetaRNN

Benign

0.20

T;T

MetaSVM

Benign

-0.96

MutationTaster

Benign

1.0

N;N

PrimateAI

Benign

0.26

PROVEAN

Pathogenic

-4.9

D;D

REVEL

Benign

0.17

Sift

Benign

0.091

T;T

Sift4G

Uncertain

0.0030

D;D

Vest4

0.29

MutPred

0.36

Loss of ubiquitination at K1489 (P = 0.0607);Loss of ubiquitination at K1489 (P = 0.0607);

MVP

0.86

MPC

0.023

ClinPred

0.41

GERP RS

0.0098

gMVP

0.32

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