rs398122741

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 4P and 1B. PM1PM2BP4

The NM_000059.4(BRCA2):​c.217C>A​(p.Gln73Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,132 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict 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. Q73P) has been classified as Uncertain significance.

Frequency

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

Consequence

BRCA2
NM_000059.4 missense

Scores

5
11

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 2.69

Publications

6 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 3 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 benign, 15 uncertain in NM_000059.4
PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.30046418).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BRCA2NM_000059.4 linkc.217C>A p.Gln73Lys missense_variant Exon 3 of 27 ENST00000380152.8 NP_000050.3 P51587

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BRCA2ENST00000380152.8 linkc.217C>A p.Gln73Lys missense_variant Exon 3 of 27 5 NM_000059.4 ENSP00000369497.3 P51587
BRCA2ENST00000614259.2 linkn.217C>A non_coding_transcript_exon_variant Exon 2 of 26 2 ENSP00000506251.1 A0A7P0TAP7
BRCA2ENST00000530893.7 linkc.-153C>A 5_prime_UTR_variant Exon 3 of 27 1 ENSP00000499438.2 A0A590UJI7

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461132
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
726916
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:
33470
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39678
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86246
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53400
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111346
Other (OTH)
AF:
0.00
AC:
0
AN:
60374
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
33
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1
Sep 22, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.Q73K variant (also known as c.217C>A), located in coding exon 2 of the BRCA2 gene, results from a C to A substitution at nucleotide position 217. The glutamine at codon 73 is replaced by lysine, an amino acid with similar properties. This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Familial cancer of breast;C2675520:Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:1
May 25, 2021
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hereditary breast ovarian cancer syndrome Uncertain:1
Sep 03, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glutamine, which is neutral and polar, with lysine, which is basic and polar, at codon 73 of the BRCA2 protein (p.Gln73Lys). 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. 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%. 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
Benign
0.094
BayesDel_addAF
Benign
-0.016
T
BayesDel_noAF
Benign
-0.26
CADD
Benign
20
DANN
Uncertain
0.99
Eigen
Uncertain
0.23
Eigen_PC
Benign
0.19
FATHMM_MKL
Uncertain
0.90
D
M_CAP
Benign
0.043
D
MetaRNN
Benign
0.30
T;T
MetaSVM
Benign
-0.97
T
PhyloP100
2.7
PrimateAI
Benign
0.40
T
PROVEAN
Benign
-0.96
N;N
REVEL
Benign
0.10
Sift
Uncertain
0.0080
D;D
Sift4G
Uncertain
0.020
D;D
Vest4
0.36
MutPred
0.34
Gain of methylation at Q73 (P = 0.0055);Gain of methylation at Q73 (P = 0.0055);
MVP
0.92
MPC
0.14
ClinPred
0.82
D
GERP RS
5.6
gMVP
0.66
Mutation Taster
=95/5
polymorphism

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

Other links and lift over

dbSNP: rs398122741; hg19: chr13-32893363; API