rs768401297

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_007294.4(BRCA1):​c.5485dupG​(p.Glu1829GlyfsTer51) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,862 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★★). Synonymous variant affecting the same amino acid position (i.e. E1829E) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

BRCA1
NM_007294.4 frameshift

Scores

Not classified

Clinical Significance

Pathogenic reviewed by expert panel P:4

Conservation

PhyloP100: 0.0840

Publications

4 publications found
Variant links:
Genes affected
BRCA1 (HGNC:1100): (BRCA1 DNA repair associated) This gene encodes a 190 kD nuclear phosphoprotein that plays a role in maintaining genomic stability, and it also acts as a tumor suppressor. The BRCA1 gene contains 22 exons spanning about 110 kb of DNA. The encoded protein combines with other tumor suppressors, DNA damage sensors, and signal transducers to form a large multi-subunit protein complex known as the BRCA1-associated genome surveillance complex (BASC). This gene product associates with RNA polymerase II, and through the C-terminal domain, also interacts with histone deacetylase complexes. This protein thus plays a role in transcription, DNA repair of double-stranded breaks, and recombination. Mutations in this gene are responsible for approximately 40% of inherited breast cancers and more than 80% of inherited breast and ovarian cancers. Alternative splicing plays a role in modulating the subcellular localization and physiological function of this gene. Many alternatively spliced transcript variants, some of which are disease-associated mutations, have been described for this gene, but the full-length natures of only some of these variants has been described. A related pseudogene, which is also located on chromosome 17, has been identified. [provided by RefSeq, May 2020]
BRCA1 Gene-Disease associations (from GenCC):
  • breast-ovarian cancer, familial, susceptibility to, 1
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • Fanconi anemia, complementation group S
    Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
  • pancreatic cancer, susceptibility to, 4
    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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 103 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 17-43045784-T-TC is Pathogenic according to our data. Variant chr17-43045784-T-TC is described in ClinVar as Pathogenic. ClinVar VariationId is 254471.Status of the report is reviewed_by_expert_panel, 3 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BRCA1NM_007294.4 linkc.5485dupG p.Glu1829GlyfsTer51 frameshift_variant Exon 23 of 23 ENST00000357654.9 NP_009225.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BRCA1ENST00000357654.9 linkc.5485dupG p.Glu1829GlyfsTer51 frameshift_variant Exon 23 of 23 1 NM_007294.4 ENSP00000350283.3

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251056
AF XY:
0.00000737
show subpopulations
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:
0.00000882
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461862
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727234
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111988
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:4
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

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

- -

Hereditary cancer-predisposing syndrome Pathogenic:1
Mar 18, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant inserts 1 nucleotide in exon 23 of the BRCA1 gene, creating a frameshift and extending the C-terminus of the variant protein by 16 amino acids compared to the reference protein. This variant alters the protein sequence starting at codon 1829 and disrupts the last 29 amino acids of the BRCT domain, that is important for phosphopeptide binding and DNA damage response (PMID: 25701377) and is therefore expected to result in a non-functional protein product. This variant has been reported in at least two individuals affected with ovarian cancer or early-onset breast cancer (PMID: 27767231, 28145423). This variant has been identified in 1/251056 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Loss of BRCA1 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:1
May 30, 2018
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. A different truncation (p.Gln1857Argfs*65) that lies downstream of this variant has been determined to be pathogenic (PMID: 21520333, 11573086, 14576433, 15133503, 25652403). This suggests that deletion of this region of the BRCA1 protein is causative of disease. This variant has been observed in an individual affected with ovarian cancer (PMID: 27767231). ClinVar contains an entry for this variant (Variation ID: 254471). This variant is present in population databases (rs768401297, ExAC 0.001%). This sequence change duplicates 1 nucleotide from exon 23 of the BRCA1 mRNA (c.5485dupG), causing a frameshift at codon 1829. This is expected to delete the last 35 amino acids of the BRCA1 protein and replace them with 15 additional amino acid residues, creating a new downstream translational stop signal in the last exon that extends the length of the protein (p.Glu1829Glyfs*51). While this is not anticipated to result in nonsense mediated decay, it may result in a disrupted BRCA1 protein. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
0.084
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

Publications

Other links and lift over

dbSNP: rs768401297; hg19: chr17-41197801; API