Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong
The NM_007294.4(BRCA1):c.5419del(p.Ile1807LeufsTer27) variant causes a frameshift 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 (★★★). Synonymous variant affecting the same amino acid position (i.e. I1807I) has been classified as Uncertain significance.
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]
Verdict is Pathogenic. Variant got 18 ACMG points.
PVS1
?
PVS1 - null variant (nonsense, frameshift, canonical ±1 or 2 splice sites, initiation codon, single or multiexon deletion) in a gene where LOF is a known mechanism of disease
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. There are 154 pathogenic variants in the truncated region.
PM2
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PM2 - Absent from controls (or at extremely low frequency if recessive) in Exome Sequencing Project, 1000 Genomes Project, or Exome Aggregation Consortium
Very rare variant in population databases, with high coverage;
PP5
?
PP5 - Reputable source recently reports variant as pathogenic, but the evidence is not available to the laboratory to perform an independent evaluation
Variant 17-43047690-AT-A is Pathogenic according to our data. Variant chr17-43047690-AT-A is described in ClinVar as [Pathogenic]. Clinvar id is 55571.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr17-43047690-AT-A is described in Lovd as [Pathogenic]. Variant chr17-43047690-AT-A is described in Lovd as [Pathogenic]. Variant chr17-43047690-AT-A is described in Lovd as [Pathogenic]. Variant chr17-43047690-AT-A is described in Lovd as [Pathogenic].
The c.5419delA pathogenic mutation, located in coding exon 21 of the BRCA1 gene, results from a deletion of one nucleotide at position 5419, causing a translational frameshift within the functionally-important BRCT2 domain and a predicted alternate stop codon. This mutation (designated as 5537delA) was identified and shown to segregate with disease in a Spanish hereditary breast/ovarian cancer family (Díez O et al. Int. J. Cancer 1999 Nov;83(4):465-9). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation. As such, this alteration is interpreted as a disease-causing mutation. -
Pathogenic, criteria provided, single submitter
clinical testing
Color Diagnostics, LLC DBA Color Health
Jan 15, 2020
This variant deletes 1 nucleotide in exon 22 of the BRCA1 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 has not been identified 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
Pathogenic, no assertion criteria provided
research
Research Molecular Genetics Laboratory, Women's College Hospital, University of Toronto