chr13-32380084-TC-AT

Position:

• chr13-32380084-TC-AT

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.9195_9196delinsAT​(p.Phe3065_Gln3066delinsLeuTer) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA2 NM_000059.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:6
• Conservation: PhyloP100: 0.858

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 13-32380084-TC-AT is Pathogenic according to our data. Variant chr13-32380084-TC-AT is described in ClinVar as [Pathogenic]. Clinvar id is 231244.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.9195_9196delinsAT	p.Phe3065_Gln3066delinsLeuTer	stop_gained	24/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.9195_9196delinsAT	p.Phe3065_Gln3066delinsLeuTer	stop_gained	24/27	5	NM_000059.4	ENSP00000369497	A2

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Apr 10, 2021	Variant summary: BRCA2 c.9195_9196delinsAT (p.Phe3065LeufsX2) 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. This variant is interpreted as a combination of two adjacent nucleotide changes in cis, namely c.9195T>A (p.Phe3065Leu) and c.9196C>T (p.Gln3066*) resulting in an annotation as c.9195_9196delinsAT. The BIC database reports two records of these variants co-occurring in the same individual. Truncations downstream of this position have been classified as pathogenic by our laboratory. Both the individual variant combinations and the joint delins variant are absent in 251286 control chromosomes. This variant, annotated as c.9195_9196delinsAT has been reported at-least once in the literature in an individual affected with breast and ovarian cancer (example, Meulemans_2020). However, c.9196C>T (p.Gln3066*) has been reported in multiple individuals affected with Hereditary Breast And Ovarian Cancer Syndrome (example, Rebbeck_2018). To our knowledge, c.9195T>A (p.Phe3065Leu) has not been reported in isolation both in the literature and at our laboratory. These data indicate that this delins variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Four 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. Some submitters cite overlapping evidence utilized in the context of this evaluation and report a similar rationale regarding the underlying variant annotation. Based on the evidence outlined above, this delins variant was classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 04, 2023	This sequence change creates a premature translational stop signal (p.Phe3065_Gln3066delinsLeu*) 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). Information on the frequency of this variant in the gnomAD database is not available, as this variant may be reported differently in the database. This premature translational stop signal has been observed in individual(s) with BRCA2-related disease (PMID: 14559878, 24504028). ClinVar contains an entry for this variant (Variation ID: 231244). For these reasons, this variant has been classified as Pathogenic. -

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

Pathogenic, criteria provided, single submitter

clinical testing

Counsyl

Apr 13, 2016

- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Quest Diagnostics Nichols Institute San Juan Capistrano

Nov 14, 2019

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 not found in general population data. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 23, 2019

The c.9195_9196delTCinsAT pathogenic mutation, located in coding exon 23 of the BRCA2 gene, results from the deletion of TC and insertion of AT between nucleotide positions 9195 and 9196. This changes the amino acid from a glutamine to a stop codon at amino acid position 3066. 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. -

Familial cancer of breast Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

MGZ Medical Genetics Center

Oct 12, 2021

- -

Computational scores

Source: dbNSFP v4.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs876659047; hg19: chr13-32954221;