Despite the prevailing view at the time that most cancers were caused by viruses, Mary-Claire King, now at the University of Washington, noticed that women in some families were more likely to get breast cancer than others, kicking off her search for the BRCA gene, as she recounts to NPR's Audie Cornish.
"Some families were at high risk of the disease, but without an explanation why that could be true. In the absence of any other explanation I was driven to turn to genetics," King says.
It took a while — in the days before the Human Genome Project — but by 1990, King says they had incontrovertible proof that there was a gene that lived in a particular spot on chromosome 17. The gene was then cloned in 1994, 20 years ago.
King also tells Cornish that as she started out, she had a sort of freedom in her work because she was ignored. "As a young scientist, it can be liberating to not have expectations placed on you," King says. "If you can work quietly, if you can obtain funds for your work … I could work in a way that allowed me the time and space to develop evidence until I was convinced of it."
"Once … you present [your evidence] then of course you're no longer being ignored. You're being attacked from all sides. Then you need to defend your evidence," she adds. "But if you've had 17 years to do it, to build it, you're in a much better position to defend it well."