What this gene does
BRCA1 helps repair a specific kind of DNA damage: breaks through both strands. Inherit a broken copy and your cells repair such damage less well, and cancer risk rises substantially. It matters to gene editing for a reason people find surprising: the repair pathway BRCA1 works in is the same one CRISPR relies on when it makes a precise correction.
BRCA1, at 17q21.31, encodes a tumour suppressor central to homologous recombination repair of double-strand breaks. Pathogenic variants confer substantially elevated lifetime risk of breast and ovarian cancer. Its relevance to editing is mechanistic: homology-directed repair, the pathway required for template-based correction after a Cas9 cut, is the pathway BRCA1 serves — and it operates only in dividing cells, which is a fundamental constraint on precise editing.
Sources
- MedlinePlus Genetics, U.S. National Library of Medicine
BRCA1 gene ↗