To help clinicians and patients obtain better information about the breast or ovarian cancer risks posed by specific mutations in the BRCA1 gene, Greg Findlay, an M.D./Ph.d. student at the University of Washington School of Medicine developed a research approach called saturation genome editing.

This method relies on CRISPR, an enzyme tool that cuts strands of DNA to modify its sequence.  With it, they made thousands of miniscule revisions in the BRCA1 gene, even changes that have not yet been seen in a human. Then the scientists measured the effects of each mutation to see which ones caused problems in human cells growing in a dish.  

The results and data are now being made available to assist women and their physicians in determining whether their genetic test results indicate a potentially harmful or harmless variant in the BRCA1 gene.  

Jay Shendure and Lea Starita of the Department of Genome Sciences at the UW School of Medicine explain the significance of the findings reported today in Nature.  Shendure directs the Brotman Baty Institute for Precision Medicine in Seattle, and Starita co-directs the Brotman Baty Advanced Technology Lab.  Findlay and his colleagues conducted the newly published research in their laboratories, along with collaborators in other units. 

Access the downloadable video.