ClinVar

Description

This missense variant replaces serine with cysteine at codon 3291 of the BRCA2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). The reference amino acid, serine 3291, has been reported to be important for homology-mediated DNA repair (PMID: 15800615, 22194698). However, a functional study in BRCA2-deficient mouse embryonic stem cell reported no impact on cell viability, homology-mediated DNA repair activity, or cisplatin sensitivity (PMID: 29988080). Additional functional studies have reported increased sensitivity to some PARP inhibitors (PMID: 32444794) and reduced RAD51 interaction in a mammalian two-hybrid assay (PMID: 35409418). This variant has been observed in individuals affected with breast cancer and in healthy individuals (PMID: 25452441, 29341116, 33471991). In a large breast cancer case-control meta analysis conducted by the BRIDGES consortium, this variant was reported in 1/60466 cases and 2/53461 unaffected controls (PMID: 33471991; Leiden Open Variation Database DB-ID BRCA2_008826). This variant has been identified in 26/282584 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance.