NM_000059.4:c.6600_6601delTT

Variant names:

• chr13-32340951-CTT-C
• rs80359607
• NM_000059.4:c.6600_6601delTT

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000059.4(BRCA2):​c.6600_6601delTT​(p.Ser2201fs) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,456,934 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: BRCA2 NM_000059.4 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:14
• Conservation: PhyloP100: 1.15

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]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 13-32340951-CTT-C is Pathogenic according to our data. Variant chr13-32340951-CTT-C is described in ClinVar as [Pathogenic]. Clinvar id is 52131.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32340951-CTT-C is described in Lovd as [Pathogenic]. Variant chr13-32340951-CTT-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.6600_6601delTT	p.Ser2201fs	frameshift_variant	Exon 11 of 27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.6600_6601delTT	p.Ser2201fs	frameshift_variant	Exon 11 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.6231_6232delTT	p.Ser2078fs	frameshift_variant	Exon 11 of 27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.6600_6601delTT		non_coding_transcript_exon_variant	Exon 10 of 26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000408 AC: 1 AN: 245136 Hom.: 0 AF XY: 0.00000754 AC XY: 1 AN XY: 132558

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000300

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: 1456934 Hom.: 0 AF XY: 0.00000276 AC XY: 2 AN XY: 724438

Gnomad4 AFR exome AF: 0.00

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:14

Revision: reviewed by expert panel

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 2 Pathogenic:5

Jan 01, 2017

Genologica Medica

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Sep 08, 2016

Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA)

Significance: Pathogenic

Review Status: reviewed by expert panel

Collection Method: curation

Variant allele predicted to encode a truncated non-functional protein. -

Oct 02, 2015

Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), c/o University of Cambridge

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Dec 22, 2010

Sharing Clinical Reports Project (SCRP)

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Feb 20, 2004

Breast Cancer Information Core (BIC) (BRCA2)

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

not provided Pathogenic:2

Oct 23, 2023

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Observed in individuals with BRCA2-related cancers (PMID: 22798144, 19491284, 24010542, 29884136); Not observed at significant frequency in large population cohorts (gnomAD); Truncating variants in this gene are considered pathogenic by a well-established clinical consortium and/or database; Also known as 6828_6829delTT; This variant is associated with the following publications: (PMID: 22798144, 24010542, 19491284, 26300996, 31447099, 30787465, 28179634, 30425037, 29446198, 34308104, 34645131, 30720243, 28111427, 32467295, 29922827, 29884136, 32719484) -

Jul 17, 2020

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The variant creates a premature nonsense codon, and is therefore predicted to result in the loss of a functional protein. Found in at least one patient with expected phenotype for this gene, and found in general population data at a frequency that is consistent with pathogenicity. -

Hereditary cancer-predisposing syndrome Pathogenic:2

Mar 13, 2024

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.6600_6601delTT pathogenic mutation, located in coding exon 10 of the BRCA2 gene, results from a deletion of two nucleotides at nucleotide positions 6600 to 6601, causing a translational frameshift with a predicted alternate stop codon (p.S2201*). This mutation has been reported in multiple hereditary breast and ovarian cancer (HBOC) patients (Haffty BG et al, 2009 Oct;20:1653-9; Kim H et al. Breast Cancer Res Treat, 2012 Aug;134:1315-26; Konstantopoulou I et al. Clin Genet, 2014 Jan;85:36-42; Park JS et al. Cancer Res Treat, 2017 Oct;49:1012-1021; Rebbeck TR et al. Hum Mutat, 2018 05;39:593-620). Of note, this alteration is also designated as 6828delTT in the published literature. In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Feb 22, 2022

Color Diagnostics, LLC DBA Color Health

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant deletes 2 nucleotides in exon 11 of the BRCA2 gene, creating a frameshift and premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. This variant is also known as 6828delTT based on Breast Cancer Information Core (BIC) nomenclature. This variant has been reported in individuals affected with breast and/or ovarian cancer (PMID: 19491284, 22798144, 24010542, 29884136; Color internal data). This variant has been identified in 1/245136 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Loss of BRCA2 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -

Hereditary breast ovarian cancer syndrome Pathogenic:2

Aug 19, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Ser2201*) in the BRCA2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in BRCA2 are known to be pathogenic (PMID: 20104584). This variant is present in population databases (rs80359607, gnomAD 0.003%). This premature translational stop signal has been observed in individual(s) with early onset breast cancer (PMID: 19491284). This variant is also known as 6828delTT. ClinVar contains an entry for this variant (Variation ID: 52131). For these reasons, this variant has been classified as Pathogenic. -

Oct 11, 2019

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: BRCA2 c.6600_6601delTT (p.Ser2201X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory. The variant allele was found at a frequency of 4.1e-06 in 245882 control chromosomes. c.6600_6601delTT has been reported in the literature in multiple individuals affected with Hereditary Breast and Ovarian Cancer (Haffty_2009, Kim_2012, Konstantopoulou_2014, Ahmadloo_2017, Pajares_2018, Lin_2019). These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Seven clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Medulloblastoma;C0346153:Familial cancer of breast;C0376358:Malignant tumor of prostate;C1838457:Fanconi anemia complementation group D1;C2675520:Breast-ovarian cancer, familial, susceptibility to, 2;C2751641:Glioma susceptibility 3;C3150546:Pancreatic cancer, susceptibility to, 2;CN033288:Wilms tumor 1 Pathogenic:1

Apr 19, 2022

Fulgent Genetics, Fulgent Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

BRCA2-related disorder Pathogenic:1

Mar 07, 2024

PreventionGenetics, part of Exact Sciences

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

The BRCA2 c.6600_6601delTT variant is predicted to result in premature protein termination (p.Ser2201*). This variant has been reported in multiple individuals with breast cancer (see for example, Table 3, Haffty et al. 2009. PubMed ID: 19491284; Table S1, Park et al. 2017. PubMed ID: 28111427; Table 2, Konstantopoulou et al. 2013. PubMed ID: 24010542). This variant is reported in 0.0030% of alleles in individuals of Latino descent in gnomAD. This variant has been classified as pathogenic by an expert panel in the ClinVar database (https://www.ncbi.nlm.nih.gov/clinvar/variation/52131/). Nonsense variants in BRCA2 are expected to be pathogenic. This variant is interpreted as pathogenic. -

Familial cancer of breast Pathogenic:1

Apr 04, 2022

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

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

Other links and lift over

dbSNP: rs80359607; hg19: chr13-32915088;