13-32316526-A-T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_000059.4(BRCA2):​c.66A>T​(p.Ala22Ala) variant causes a splice region, synonymous change. The variant allele was found at a frequency of 0.000000685 in 1,460,848 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A22A) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

BRCA2
NM_000059.4 splice_region, synonymous

Scores

2
Splicing: ADA: 0.9999
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 5.07

Publications

0 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: Likely_pathogenic. The variant received 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BRCA2NM_000059.4 linkc.66A>T p.Ala22Ala splice_region_variant, synonymous_variant Exon 2 of 27 ENST00000380152.8 NP_000050.3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BRCA2ENST00000380152.8 linkc.66A>T p.Ala22Ala splice_region_variant, synonymous_variant Exon 2 of 27 5 NM_000059.4 ENSP00000369497.3
BRCA2ENST00000614259.2 linkn.66A>T splice_region_variant, non_coding_transcript_exon_variant Exon 1 of 26 2 ENSP00000506251.1
BRCA2ENST00000530893.7 linkc.-303+3A>T splice_region_variant, intron_variant Intron 2 of 26 1 ENSP00000499438.2

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460848
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
726760
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33448
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26120
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39680
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86202
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53406
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5760
European-Non Finnish (NFE)
AF:
9.00e-7
AC:
1
AN:
1111166
Other (OTH)
AF:
0.00
AC:
0
AN:
60346
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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.:
33

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2
Oct 25, 2023
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This synonymous variant causes a A>T nucleotide change in the BRCA2 gene. Splice site prediction tools suggest that this variant may impact RNA splicing. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in a multifactorial analysis with co-occurrence and family history likelihood ratios for pathogenicity of 1.0246 and 0.9357, respectively (PMID: 31131967). 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. -

Apr 15, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.66A>T variant (also known as p.A22A), located in coding exon 1 of the BRCA2 gene, results from an A to T substitution at nucleotide position 66. This nucleotide substitution does not change the alanine at codon 22. This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration may weaken the native splice donor site; however, direct evidence is insufficient at this time (Ambry internal data). Based on the available evidence, the clinical significance of this variant remains unclear. -

not specified Uncertain:1
Dec 05, 2016
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:1
Nov 20, 2023
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This synonymous variant causes a A>T nucleotide change in the BRCA2 gene. Splice site prediction tools suggest that this variant may impact RNA splicing. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in a multifactorial analysis with co-occurrence and family history likelihood ratios for pathogenicity of 1.0246 and 0.9357, respectively (PMID: 31131967). 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:1
Oct 08, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. RNA analysis performed to evaluate the impact of this variant on mRNA splicing indicates it does not significantly alter splicing (Invitae). ClinVar contains an entry for this variant (Variation ID: 438999). This variant has not been reported in the literature in individuals affected with BRCA2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change affects codon 22 of the BRCA2 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the BRCA2 protein. It affects a nucleotide within the consensus splice site. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.24
CADD
Benign
22
DANN
Benign
0.95
PhyloP100
5.1
PromoterAI
0.0056
Neutral

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.99
SpliceAI score (max)
0.43
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.43
Position offset: 1

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

Publications

Other links and lift over

dbSNP: rs1555280115; hg19: chr13-32890663; API