13-32380098-C-T

Variant names:

• chr13-32380098-C-T
• rs747837583
• NM_000059.4:c.9209C>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM1

The NM_000059.4(BRCA2):​c.9209C>T​(p.Ser3070Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000116 in 1,461,768 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. S3070P) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.000012 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6 B:1
• Conservation: PhyloP100: 2.04
• Publications: 8 publications found

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

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 17 benign, 22 uncertain in NM_000059.4

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.9209C>T	p.Ser3070Phe	missense_variant	Exon 24 of 27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.9209C>T	p.Ser3070Phe	missense_variant	Exon 24 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.8840C>T	p.Ser2947Phe	missense_variant	Exon 24 of 27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.*1267C>T		non_coding_transcript_exon_variant	Exon 23 of 26	2		ENSP00000506251.1
BRCA2	ENST00000614259.2	n.*1267C>T		3_prime_UTR_variant	Exon 23 of 26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251282 AF XY: 0.00000736

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000116 AC: 17 AN: 1461768 Hom.: 0 Cov.: 32 AF XY: 0.0000151 AC XY: 11 AN XY: 727184

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39666

South Asian (SAS) AF: 0.00 AC: 0 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.0000144 AC: 16 AN: 1111960

Other (OTH) AF: 0.0000166 AC: 1 AN: 60386

GnomAD4 genome Cov.: 33

TwinsUK AF: 0.000270 AC: 1

ALSPAC AF: 0.00 AC: 0

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:6 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Uncertain:2

Dec 16, 2020

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

May 10, 2017

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is denoted BRCA2 c.9209C>T at the cDNA level, p.Ser3070Phe (S3070F) at the protein level, and results in the change of a Serine to a Phenylalanine (TCT>TTT). Using alternate nomenclature, this variant would be defined as BRCA2 9437C>T. This variant has not, to our knowledge, been published in the literature as pathogenic or benign. BRCA2 Ser3070Phe was not observed in large population cohorts (NHLBI Exome Sequencing Project, The 1000 Genomes Consortium 2015, Lek 2016). Since Serine and Phenylalanine differ in polarity, charge, size or other properties, this is considered a non-conservative amino acid substitution. BRCA2 Ser3070Phe occurs at a position that is not conserved and is located in the DNA binding domain (Yang 2002). In silico analyses are inconsistent regarding the effect this variant may have on protein structure and function. Based on currently available evidence, it is unclear whether BRCA2 Ser3070Phe is a pathogenic or benign variant. We consider it to be a variant of uncertain significance.

Hereditary cancer-predisposing syndrome Uncertain:1 Benign:1

Jan 11, 2022

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.

Jun 23, 2023

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces serine with phenylalanine at codon 3070 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 shown that this variant does not impact homology-directed DNA repair activity (PMID: 35736817). This variant has been reported in at least two individuals affected with breast cancer and an individual affected with prostate cancer (PMID: 25186627, 31214711, 33471991; Leiden Open Variation Database DB-ID BRCA2_007515). One individual affected with breast cancer also carried a pathogenic variant in the CHEK2 gene that could explain the observed phenotype (PMID: 25186627). This variant has been identified in 1/251282 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.

Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:1

Jul 10, 2023

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 serine with phenylalanine at codon 3070 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 shown that this variant does not impact homology-directed DNA repair activity (PMID: 35736817). This variant has been reported in at least two individuals affected with breast cancer and an individual affected with prostate cancer (PMID: 25186627, 31214711, 33471991; Leiden Open Variation Database DB-ID BRCA2_007515). One individual affected with breast cancer also carried a pathogenic variant in the CHEK2 gene that could explain the observed phenotype (PMID: 25186627). This variant has been identified in 1/251282 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.

Familial cancer of breast Uncertain:1

Sep 07, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Hereditary breast ovarian cancer syndrome Uncertain:1

Jun 23, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine, which is neutral and polar, with phenylalanine, which is neutral and non-polar, at codon 3070 of the BRCA2 protein (p.Ser3070Phe). This variant is present in population databases (rs747837583, gnomAD 0.0009%). 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: 186691). 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	Benign	0.17
BayesDel_addAF	Uncertain	0.14	D
BayesDel_noAF	Uncertain	-0.030
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Benign	0.0	.;.
Eigen	Uncertain	0.40
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Benign	0.0	.;.
M_CAP	Pathogenic	0.31	D
MetaRNN	Uncertain	0.61	D;D
MetaSVM	Uncertain	0.48	D
MutationAssessor	Benign	0.0	.;.
PhyloP100		2.0
PrimateAI	Benign	0.39	T
PROVEAN	Benign	-1.4	N;N
REVEL	Uncertain	0.57
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.0040	D;D
Vest4		0.47
ClinPred		0.89	D
GERP RS		4.7
gMVP		0.43
Mutation Taster		=80/20	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

Other links and lift over

dbSNP: rs747837583; hg19: chr13-32954235;