Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2
The NM_007294.4(BRCA1):c.3965A>T(p.Lys1322Ile) variant causes a missense 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K1322E) has been classified as Likely benign.
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]
Likely benign, criteria provided, single submitter
curation
University of Washington Department of Laboratory Medicine, University of Washington
Mar 23, 2023
Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673). -
Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
May 09, 2024
The p.K1322I variant (also known as c.3965A>T), located in coding exon 9 of the BRCA1 gene, results from an A to T substitution at nucleotide position 3965. The lysine at codon 1322 is replaced by isoleucine, an amino acid with dissimilar properties. This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear. -
Breast-ovarian cancer, familial, susceptibility to, 1 Uncertain:1
Uncertain significance, no assertion criteria provided
clinical testing
Breast Cancer Information Core (BIC) (BRCA1)
Nov 25, 2004
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not provided Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
Quest Diagnostics Nichols Institute San Juan Capistrano
Jan 28, 2018
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Hereditary breast ovarian cancer syndrome Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
Invitae
Jan 18, 2024
This sequence change replaces lysine, which is basic and polar, with isoleucine, which is neutral and non-polar, at codon 1322 of the BRCA1 protein (p.Lys1322Ile). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with BRCA1-related conditions. ClinVar contains an entry for this variant (Variation ID: 55060). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt BRCA1 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -