rs397507881

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM2PM5PP3_StrongPP5

The NM_000059.4(BRCA2):​c.67G>A​(p.Asp23Asn) variant causes a missense, splice region change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. 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. D23Y) has been classified as Pathogenic.

Frequency

Genomes: not found (cov: 33)

Consequence

BRCA2
NM_000059.4 missense, splice_region

Scores

5
4
7
Splicing: ADA: 1.000
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:2

Conservation

PhyloP100: 5.43
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]

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ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr13-32316527-G-T is described in Lovd as [Pathogenic].
PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
Variant 13-32316527-G-A is Pathogenic according to our data. Variant chr13-32316527-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 225732.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=2}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BRCA2NM_000059.4 linkc.67G>A p.Asp23Asn missense_variant, splice_region_variant Exon 2 of 27 ENST00000380152.8 NP_000050.3 P51587

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BRCA2ENST00000380152.8 linkc.67G>A p.Asp23Asn missense_variant, splice_region_variant Exon 2 of 27 5 NM_000059.4 ENSP00000369497.3 P51587
BRCA2ENST00000530893.7 linkc.-303+4G>A splice_region_variant, intron_variant Intron 2 of 26 1 ENSP00000499438.2 A0A590UJI7
BRCA2ENST00000614259.2 linkn.67G>A splice_region_variant, non_coding_transcript_exon_variant Exon 1 of 26 2 ENSP00000506251.1 A0A7P0TAP7

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
Cov.:
31
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 2 Pathogenic:1
Apr 21, 2016
Michigan Medical Genetics Laboratories, University of Michigan
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Uncertain:1
Nov 20, 2024
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.67G>A variant (also known as p.D23N), located in coding exon 1 of the BRCA2 gene, results from a G to A substitution at nucleotide position 67. The amino acid change results in aspartic acid to asparagine at codon 23, an amino acid with highly similar properties. However, this change occurs in the last base pair of coding exon 1, which makes it likely to have some effect on normal mRNA splicing. This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice donor site and will result in the creation or strengthening of a novel splice donor site. RNA studies have shown this alteration to result in a novel donor gain which causes a frameshift (Fraile-Bethencourt, E et al. J Pathol 2019 Aug;248(4):409-420; Leman R et al. Nucleic Acids Res, 2018 Sep;46:7913-7923; Ambry internal data). Based on the available evidence, the clinical significance of this variant remains unclear. -

Hereditary breast ovarian cancer syndrome Uncertain:1
Apr 23, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant also falls at the last nucleotide of exon 2 of the BRCA2 coding sequence, which is part of the consensus splice site for this exon. This variant has been reported in an individual affected with breast cancer (PMID: 24156927). ClinVar contains an entry for this variant (Variation ID: 225732). Nucleotide substitutions within the consensus splice site are relatively common causes of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of nucleotide changes on RNA splicing suggest that this variant may alter RNA splicing, but this prediction has not been confirmed by published transcriptional studies. This variant is not present in population databases (ExAC no frequency). In summary, this variant is a rare change with uncertain impact on protein function. While it is absent from the population and reported in affected individuals, the available evidence is currently insufficient to determine its role 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
0.33
BayesDel_addAF
Benign
-0.048
T
BayesDel_noAF
Benign
-0.31
CADD
Pathogenic
36
DANN
Pathogenic
1.0
Eigen
Pathogenic
0.71
Eigen_PC
Pathogenic
0.67
FATHMM_MKL
Uncertain
0.89
D
M_CAP
Uncertain
0.13
D
MetaRNN
Benign
0.41
T;T
MetaSVM
Uncertain
-0.27
T
PrimateAI
Uncertain
0.57
T
PROVEAN
Benign
-1.2
N;N
REVEL
Benign
0.15
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Vest4
0.46
MutPred
0.34
Loss of ubiquitination at K21 (P = 0.0516);Loss of ubiquitination at K21 (P = 0.0516);
MVP
0.94
MPC
0.13
ClinPred
0.99
D
GERP RS
5.1
gMVP
0.57

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
1.0
SpliceAI score (max)
0.58
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.51
Position offset: -4
DS_DL_spliceai
0.58
Position offset: 0

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.

Other links and lift over

dbSNP: rs397507881; hg19: chr13-32890664; COSMIC: COSV61525617; COSMIC: COSV61525617; API