rs879255335

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_000059.4(BRCA2):​c.6888A>G​(p.Ile2296Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000699 in 1,431,494 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I2296L) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 7.0e-7 ( 0 hom. )

Consequence

BRCA2
NM_000059.4 missense

Scores

3
13

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 2.37

Publications

4 publications found
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 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.23661587).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BRCA2NM_000059.4 linkc.6888A>G p.Ile2296Met missense_variant Exon 12 of 27 ENST00000380152.8 NP_000050.3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BRCA2ENST00000380152.8 linkc.6888A>G p.Ile2296Met missense_variant Exon 12 of 27 5 NM_000059.4 ENSP00000369497.3
BRCA2ENST00000530893.7 linkc.6519A>G p.Ile2173Met missense_variant Exon 12 of 27 1 ENSP00000499438.2
BRCA2ENST00000614259.2 linkn.6888A>G non_coding_transcript_exon_variant Exon 11 of 26 2 ENSP00000506251.1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.99e-7
AC:
1
AN:
1431494
Hom.:
0
Cov.:
28
AF XY:
0.00
AC XY:
0
AN XY:
713812
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
32692
American (AMR)
AF:
0.00
AC:
0
AN:
44578
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25850
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39444
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85560
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53282
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5706
European-Non Finnish (NFE)
AF:
9.22e-7
AC:
1
AN:
1085010
Other (OTH)
AF:
0.00
AC:
0
AN:
59372
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.225
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2
Dec 16, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.I2296M variant (also known as c.6888A>G), located in coding exon 11 of the BRCA2 gene, results from an A to G substitution at nucleotide position 6888. The isoleucine at codon 2296 is replaced by methionine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Dec 05, 2023
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces isoleucine with methionine at codon 2296 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 not been reported in individuals affected with BRCA2-related disorders in the literature. 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. -

Hereditary breast ovarian cancer syndrome Uncertain:2
Jan 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 2296 of the BRCA2 protein (p.Ile2296Met). 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: 252458). 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. -

Oct 30, 2015
Genomic Diagnostic Laboratory, Division of Genomic Diagnostics, Children's Hospital of Philadelphia
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
May 04, 2022
Mendelics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

BRCA2-related cancer predisposition Uncertain:1
Aug 13, 2024
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces isoleucine with methionine at codon 2296 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 not been reported in individuals affected with BRCA2-related disorders in the literature. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.090
BayesDel_addAF
Uncertain
0.096
D
BayesDel_noAF
Benign
-0.10
CADD
Uncertain
24
DANN
Uncertain
0.99
Eigen
Benign
-0.12
Eigen_PC
Benign
-0.030
FATHMM_MKL
Benign
0.48
N
M_CAP
Benign
0.038
D
MetaRNN
Benign
0.24
T;T
MetaSVM
Benign
-0.45
T
PhyloP100
2.4
PrimateAI
Benign
0.43
T
PROVEAN
Benign
-0.68
N;N
REVEL
Uncertain
0.45
Sift
Benign
0.19
T;T
Sift4G
Benign
0.30
T;T
Vest4
0.44
MutPred
0.22
Gain of disorder (P = 0.1029);Gain of disorder (P = 0.1029);
MVP
0.82
MPC
0.15
ClinPred
0.85
D
GERP RS
5.0
gMVP
0.16
Mutation Taster
=90/10
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.050
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs879255335; hg19: chr13-32918741; API