13-32379894-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM5

The NM_000059.4(BRCA2):​c.9098C>T​(p.Thr3033Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,613,492 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. T3033?) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

BRCA2
NM_000059.4 missense

Scores

9
5
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:8B:1

Conservation

PhyloP100: 7.31
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM5
Other missense variant is known to change same aminoacid residue: Variant chr13-32379893-ACT-AA is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BRCA2NM_000059.4 linkc.9098C>T p.Thr3033Ile missense_variant Exon 23 of 27 ENST00000380152.8 NP_000050.3 P51587

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BRCA2ENST00000380152.8 linkc.9098C>T p.Thr3033Ile missense_variant Exon 23 of 27 5 NM_000059.4 ENSP00000369497.3 P51587
BRCA2ENST00000530893.7 linkc.8729C>T p.Thr2910Ile missense_variant Exon 23 of 27 1 ENSP00000499438.2 A0A590UJI7
BRCA2ENST00000614259.2 linkn.*1156C>T non_coding_transcript_exon_variant Exon 22 of 26 2 ENSP00000506251.1 A0A7P0TAP7
BRCA2ENST00000614259 linkn.*1156C>T 3_prime_UTR_variant Exon 22 of 25 2 ENSP00000506251.1 A0A7P0TAP7

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152162
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000401
AC:
1
AN:
249408
Hom.:
0
AF XY:
0.00000741
AC XY:
1
AN XY:
134956
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:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000890
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461330
Hom.:
0
Cov.:
32
AF XY:
0.00000550
AC XY:
4
AN XY:
726946
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:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000630
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152162
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74334
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.000288
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000434
Hom.:
0
Bravo
AF:
0.0000113

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:8Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2Benign:1
Oct 25, 2023
Color Diagnostics, LLC DBA Color Health
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This missense variant replaces threonine with isoleucine at codon 3033 of the BRCA2 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). A functional study has reported that this variant does not impact BRCA2 function in a homology-directed repair assay (PMID: 29394989). This variant has been reported in at least three individuals affected with breast and/or ovarian cancer (PMID: 25452441, 26153499, 33471991; Leiden Open Variation Database DB-ID BRCA2_007511). This variant has been identified in 1/249408 chromosomes 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. -

Feb 18, 2022
Sema4, Sema4
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: curation

- -

Mar 04, 2020
Ambry Genetics
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:2
Apr 08, 2009
Sharing Clinical Reports Project (SCRP)
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jan 11, 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 threonine with isoleucine at codon 3033 of the BRCA2 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). A functional study has reported that this variant does not impact BRCA2 function in a homology-directed repair assay (PMID: 29394989). This variant has been reported in at least three individuals affected with breast and/or ovarian cancer (PMID: 25452441, 26153499, 33471991; Leiden Open Variation Database DB-ID BRCA2_007511). This variant has been identified in 1/249408 chromosomes 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. -

not provided Uncertain:2
Oct 14, 2020
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The frequency of this variant in the general population, 0.000004 (1/249408 chromosomes, http://gnomad.broadinstitute.org), is uninformative in assessment of its pathogenicity. In the published literature, the variant has been reported in individuals with breast and/or ovarian cancer (PMIDs: 26153499 (2015), 25452441 (2015), and 33471991 (2021), see also LOVD (https://databases.lovd.nl/shared/variants/BRCA2)). Additionally, functional studies report inconclusive results regarding the variant’s effects on repair activity (PMIDs: 29394989 (2018), 24323938 (2014), and 23108138 (2013)). 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 damaging. Based on the available information, we are unable to determine the clinical significance of this variant. -

Jun 01, 2018
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant is denoted BRCA2 c.9098C>T at the cDNA level, p.Thr3033Ile (T3033I) at the protein level, and results in the change of a Threonine to an Isoleucine (ACT>ATT). Using alternate nomenclature, this variant would be defined as BRCA2 9326C>T. This variant has been reported in individuals with personal and/or family history of breast cancer and ovarian cancer, and exhibited an intermediate level of homology-directed repair (HDR) activity in a cell-based functional assay (Guidugli 2013, Eccles 2015, Couch 2015, Guidugli 2018). BRCA2 Thr3033Ile was not observed in large population cohorts (Lek 2016). BRCA2 Thr3033Ile is located in the DNA binding domain (Yang 2002). In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function. Based on currently available information, it is unclear whether BRCA2 Thr3033Ile is pathogenic or benign. We consider it to be a variant of uncertain significance. -

not specified Uncertain:1
Jan 20, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: BRCA2 c.9098C>T (p.Thr3033Ile) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 249408 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.9098C>T has been reported in the literature in individuals affected with Hereditary Breast and/or Ovarian Cancer (examples: Couch_2015 and Eccles_2015). These reports do not provide unequivocal conclusions about association of the variant with Hereditary Breast And Ovarian Cancer Syndrome. At least one publication reports experimental evidence evaluating an impact on protein function. This variant was described as likely neutral using HDR assay (Guidugli_2018). Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and described the variant as likely benign (n=1) and as a variant of uncertain significance (n=4). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Hereditary breast ovarian cancer syndrome Uncertain:1
Nov 10, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 3033 of the BRCA2 protein (p.Thr3033Ile). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This missense change has been observed in individual(s) with breast cancer and ovarian cancer (PMID: 25452441, 26153499). ClinVar contains an entry for this variant (Variation ID: 96879). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt BRCA2 protein function with a negative predictive value of 95%. Experimental studies have shown that this missense change does not substantially affect BRCA2 function (PMID: 23108138, 24323938, 29394989). 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
Pathogenic
0.88
BayesDel_addAF
Pathogenic
0.32
D
BayesDel_noAF
Pathogenic
0.22
CADD
Pathogenic
26
DANN
Uncertain
1.0
Eigen
Pathogenic
0.92
Eigen_PC
Pathogenic
0.88
FATHMM_MKL
Pathogenic
0.99
D
M_CAP
Pathogenic
0.31
D
MetaRNN
Uncertain
0.63
D;D
MetaSVM
Uncertain
0.51
D
PrimateAI
Uncertain
0.55
T
PROVEAN
Benign
-1.6
N;N
REVEL
Uncertain
0.58
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Vest4
0.64
MutPred
0.34
Loss of disorder (P = 0.0407);Loss of disorder (P = 0.0407);
MVP
0.97
MPC
0.17
ClinPred
0.94
D
GERP RS
5.7
gMVP
0.77

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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.

Other links and lift over

dbSNP: rs431825374; hg19: chr13-32954031; COSMIC: COSV105932272; COSMIC: COSV105932272; API