NM_000059.4:c.1804G>T

Variant names:

• chr13-32333282-G-T
• rs80358466
• NM_000059.4:c.1804G>T

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000059.4(BRCA2):​c.1804G>T​(p.Gly602*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000689 in 1,450,810 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. G602G) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: BRCA2 NM_000059.4 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 2.46
• Publications: 23 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: Pathogenic. The variant received 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 13-32333282-G-T is Pathogenic according to our data. Variant chr13-32333282-G-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 942890.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000059.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BRCA2	NM_000059.4	MANE Select	c.1804G>T	p.Gly602*	stop_gained	Exon 10 of 27	NP_000050.3
	BRCA2	NM_001432077.1		c.1804G>T	p.Gly602*	stop_gained	Exon 10 of 27	NP_001419006.1
	BRCA2	NM_001406720.1		c.1804G>T	p.Gly602*	stop_gained	Exon 10 of 27	NP_001393649.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BRCA2	ENST00000380152.8	TSL:5 MANE Select	c.1804G>T	p.Gly602*	stop_gained	Exon 10 of 27	ENSP00000369497.3
	BRCA2	ENST00000544455.6	TSL:1	c.1804G>T	p.Gly602*	stop_gained	Exon 10 of 27	ENSP00000439902.1
	BRCA2	ENST00000530893.7	TSL:1	c.1435G>T	p.Gly479*	stop_gained	Exon 10 of 27	ENSP00000499438.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.89e-7 AC: 1 AN: 1450810 Hom.: 0 Cov.: 35 AF XY: 0.00 AC XY: 0 AN XY: 721496

African (AFR) AF: 0.00 AC: 0 AN: 32554

American (AMR) AF: 0.00 AC: 0 AN: 42020

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25700

East Asian (EAS) AF: 0.00 AC: 0 AN: 39620

South Asian (SAS) AF: 0.00 AC: 0 AN: 83512

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53208

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5698

European-Non Finnish (NFE) AF: 9.02e-7 AC: 1 AN: 1108672

Other (OTH) AF: 0.00 AC: 0 AN: 59826

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Pathogenic:2

Apr 25, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 942890). This variant has not been reported in the literature in individuals affected with BRCA2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Gly602*) 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).

Oct 14, 2019

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Gly602X variant in BRCA2 has not been previously reported in individuals with hereditary breast and/or ovarian cancer (HBOC) and was absent from large population studies. This nonsense variant leads to a premature termination codon at position 602, which is predicted to lead to a truncated or absent protein. Loss of function of the BRCA2 gene is an established disease mechanism in autosomal dominant HBOC. In summary, although additional studies are required to fully establish its clinical significance, this variant meets criteria to be classified as likely pathogenic for autosomal dominant HBOC. ACMG/AMP Criteria applied: PVS1, PM2.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	35
DANN	Uncertain	0.99
Eigen	Pathogenic	0.74
Eigen_PC	Uncertain	0.53
FATHMM_MKL	Uncertain	0.92	D
PhyloP100		2.5
Vest4		0.86
GERP RS		3.6
Mutation Taster		=0/200	disease causing (ClinVar)

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: rs80358466; hg19: chr13-32907419;