Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1PM2PP3_ModeratePP5_Moderate
The NM_007294.4(BRCA1):c.5060T>G(p.Val1687Gly) variant causes a missense change. The variant allele was found at a frequency of 0.000000685 in 1,459,638 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 (★).
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 Likely_pathogenic. Variant got 8 ACMG points.
PM1
In a strand (size 3) in uniprot entity BRCA1_HUMAN there are 6 pathogenic changes around while only 1 benign (86%) in NM_007294.4
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.873
PP5
Variant 17-43067622-A-C is Pathogenic according to our data. Variant chr17-43067622-A-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 433721.Status of the report is criteria_provided_single_submitter, 1 stars.
Hereditary breast ovarian cancer syndrome Pathogenic:1
Likely pathogenic, criteria provided, single submitter
clinical testing
Cancer Variant Interpretation Group UK, Institute of Cancer Research, London
Jun 01, 2020
Data included in classification: The variant is absent from GNOMAD (PM2_sup). This variant is predicted deleterious on REVEL 0.869 (PP3_sup). The variant is non-functional on saturation genome editing in haploid BRCA1 cellular model (Findlay et al 2018, PMID: 30209399) (PS3_Strong). Classification:likely pahtogneic (exponent score: 6) Data not included in classification: Multiple other insilico tools predict as deleterious. At least 3 strong UK families: UK family #1 Maternal and paternal family history of cancer, Manchester score of >20; UK family #2 Proband with breast cancer at 48. Breast cancer in proband’s mother at 40 and 2 maternal aunts at 28 and 47; UK family #3 Proband with triple negative breast cancer at 53. -
Malignant tumor of breast Uncertain:1
Uncertain significance, no assertion criteria provided
clinical testing
Department of Pathology and Laboratory Medicine, Sinai Health System
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The BRCA1 p.Val1687Gly variant was not identified in the literature, nor was it identified in the dbSNP, NHLBI Exome Sequencing Project (Exome Variant Server), HGMD, LOVD, COSMIC, UMD, or BIC databases. The p.Val1687 residue is conserved across mammals and lower organisms, and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) suggest that the p.Val1687Gly variant may impact the protein. However, this information is not predictive enough to assume pathogenicity. In summary, based on the above information, the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of unknown significance. -
Breast-ovarian cancer, familial, susceptibility to, 1 Other:1