13-32337737-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000059.4(BRCA2):ā€‹c.3382A>Gā€‹(p.Thr1128Ala) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,356 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. T1128I) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)
Exomes š‘“: 6.8e-7 ( 0 hom. )

Consequence

BRCA2
NM_000059.4 missense

Scores

8
6
2

Clinical Significance

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

Conservation

PhyloP100: 6.88
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.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
BRCA2NM_000059.4 linkuse as main transcriptc.3382A>G p.Thr1128Ala missense_variant 11/27 ENST00000380152.8

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
BRCA2ENST00000380152.8 linkuse as main transcriptc.3382A>G p.Thr1128Ala missense_variant 11/275 NM_000059.4 A2

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD3 exomes
AF:
0.00000400
AC:
1
AN:
250046
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135336
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:
0.00000885
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461356
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
726960
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:
8.99e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32
ExAC
AF:
0.00000824
AC:
1

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
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsJul 14, 2022The p.T1128A variant (also known as c.3382A>G), located in coding exon 10 of the BRCA2 gene, results from an A to G substitution at nucleotide position 3382. The threonine at codon 1128 is replaced by alanine, an amino acid with similar properties. This amino acid position is highly 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. -
Likely benign, criteria provided, single submittercurationUniversity of Washington Department of Laboratory Medicine, University of WashingtonMar 23, 2023Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673). -
Uncertain significance, criteria provided, single submitterclinical testingColor Diagnostics, LLC DBA Color HealthMar 29, 2023This missense variant replaces threonine with alanine at codon 1128 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 been reported in a multifactorial analysis with co-occurrence and family history likelihood ratios for pathogenicity of 1.0757 and 1.210, respectively (PMID: 31131967). This variant has been identified in 1/250046 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 specified Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingGenetic Services Laboratory, University of ChicagoFeb 23, 2016- -
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpSep 23, 2022- -
not provided Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingGeneDxMar 02, 2023Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; Also known as 3610A>G; This variant is associated with the following publications: (PMID: 29884841, 32377563, 31131967) -
Uncertain significance, criteria provided, single submitterclinical testingQuest Diagnostics Nichols Institute San Juan CapistranoSep 16, 2022The variant has not been reported in the published literature. The frequency of this variant in the general population, 0.000004 (1/250046 chromosomes, http://gnomad.broadinstitute.org), is uninformative in assessment of its pathogenicity. 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. -
Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAll of Us Research Program, National Institutes of HealthOct 06, 2023This missense variant replaces threonine with alanine at codon 1128 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 been reported in a multifactorial analysis with co-occurrence and family history likelihood ratios for pathogenicity of 1.0757 and 1.210, respectively (PMID: 31131967). This variant has been identified in 1/250046 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. -
Hereditary breast ovarian cancer syndrome Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingInvitaeDec 22, 2023This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 1128 of the BRCA2 protein (p.Thr1128Ala). 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 variant has not been reported in the literature in individuals affected with BRCA2-related conditions. ClinVar contains an entry for this variant (Variation ID: 182200). 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
Pathogenic
0.73
BayesDel_addAF
Pathogenic
0.19
D
BayesDel_noAF
Uncertain
0.040
CADD
Uncertain
25
DANN
Uncertain
1.0
Eigen
Pathogenic
0.81
Eigen_PC
Pathogenic
0.78
FATHMM_MKL
Pathogenic
0.98
D
M_CAP
Pathogenic
0.33
D
MetaRNN
Uncertain
0.52
D;D
MetaSVM
Benign
-1.2
T
MutationTaster
Benign
0.99
D;D
PrimateAI
Uncertain
0.61
T
PROVEAN
Pathogenic
-4.8
D;D
REVEL
Uncertain
0.40
Sift
Pathogenic
0.0
D;D
Sift4G
Uncertain
0.0070
D;D
Vest4
0.62
MutPred
0.44
Loss of phosphorylation at T1128 (P = 0.0433);Loss of phosphorylation at T1128 (P = 0.0433);
MVP
0.93
MPC
0.17
ClinPred
0.99
D
GERP RS
5.8
gMVP
0.61

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.

Other links and lift over

dbSNP: rs730881523; hg19: chr13-32911874; API