rs144192844

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_000059.4(BRCA2):​c.1993A>G​(p.Thr665Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000373 in 1,608,024 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. T665T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

BRCA2
NM_000059.4 missense

Scores

1
15

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:9B:1

Conservation

PhyloP100: 0.711
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 Likely_benign. Variant got -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.100548774).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BRCA2NM_000059.4 linkc.1993A>G p.Thr665Ala missense_variant Exon 11 of 27 ENST00000380152.8 NP_000050.3 P51587

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BRCA2ENST00000380152.8 linkc.1993A>G p.Thr665Ala missense_variant Exon 11 of 27 5 NM_000059.4 ENSP00000369497.3 P51587
BRCA2ENST00000530893.7 linkc.1624A>G p.Thr542Ala missense_variant Exon 11 of 27 1 ENSP00000499438.2 A0A590UJI7
BRCA2ENST00000614259.2 linkn.1993A>G non_coding_transcript_exon_variant Exon 10 of 26 2 ENSP00000506251.1 A0A7P0TAP7

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152208
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000482
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.000478
GnomAD3 exomes
AF:
0.00000809
AC:
2
AN:
247100
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
133532
show subpopulations
Gnomad AFR exome
AF:
0.000124
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1455698
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
723578
show subpopulations
Gnomad4 AFR exome
AF:
0.0000303
Gnomad4 AMR exome
AF:
0.0000229
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:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152326
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74488
show subpopulations
Gnomad4 AFR
AF:
0.0000481
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.000473
Bravo
AF:
0.0000529
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:9Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3
Aug 07, 2024
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The BRCA2 c.1993A>G (p.Thr665Ala) variant has been reported in the published literature in in an individual with leukemia in a pediatric cancer study (PMID: 26580448 (2015)). This variant has also been reported to be located in a region of the BRCA2 gene that is tolerant to missense sequence changes (PMID: 31911673 (2020)). The frequency of this variant in the general population, 0.00012 (3/24846 chromosomes (Genome Aggregation Database, http://gnomad.broadinstitute.org)), is uninformative in the 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 benign. Based on the available information, we are unable to determine the clinical significance of this variant. -

Nov 22, 2019
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Has not been previously published as pathogenic or benign to our knowledge; In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Also known as 2221A>G -

Mar 17, 2015
Eurofins Ntd Llc (ga)
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Uncertain:2Benign:1
May 30, 2019
Color Diagnostics, LLC DBA Color Health
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 23, 2023
University of Washington Department of Laboratory Medicine, University of Washington
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: curation

Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673). -

Nov 20, 2022
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.T665A variant (also known as c.1993A>G), located in coding exon 10 of the BRCA2 gene, results from an A to G substitution at nucleotide position 1993. The threonine at codon 665 is replaced by alanine, an amino acid with similar properties. This amino acid position is not well 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. -

not specified Uncertain:1
Oct 05, 2023
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.1993A>G (p.Thr665Ala) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 8.1e-06 in 247100 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, c.1993A>G has not been reported in the literature in individuals affected with Hereditary Breast And Ovarian Cancer Syndrome. It has however been reported as a VUS in at-least one individual with hypodiplpoid ALL (Zhang_2015). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Breast And Ovarian Cancer Syndrome. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Eight submitters have cited clinical-significance assessments for this variant to ClinVar after 2014 (VUS, n=7; Likely benign, n=1). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:1
Jul 19, 2016
Counsyl
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

BRCA2-related cancer predisposition Uncertain:1
Aug 06, 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 alanine at codon 665 of the BRCA2 protein. Computational prediction suggests that this variant may not impact protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with hypodiploid ALL (PMID: 26580448). This variant has been identified in 2/247100 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
Jan 29, 2025
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 alanine, which is neutral and non-polar, at codon 665 of the BRCA2 protein (p.Thr665Ala). This variant is present in population databases (rs144192844, gnomAD 0.01%). 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: 141539). 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
0.10
BayesDel_addAF
Benign
-0.10
T
BayesDel_noAF
Benign
-0.15
CADD
Benign
12
DANN
Benign
0.97
Eigen
Benign
-0.37
Eigen_PC
Benign
-0.48
FATHMM_MKL
Benign
0.044
N
M_CAP
Benign
0.053
D
MetaRNN
Benign
0.10
T;T
MetaSVM
Benign
-0.84
T
PrimateAI
Benign
0.27
T
PROVEAN
Uncertain
-2.8
D;D
REVEL
Benign
0.25
Sift
Benign
0.050
D;D
Sift4G
Benign
0.071
T;T
Vest4
0.26
MVP
0.83
MPC
0.022
ClinPred
0.11
T
GERP RS
1.8
gMVP
0.21

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: rs144192844; hg19: chr13-32910485; API