Mary-Claire King

In honor of Breast Cancer Awareness Month, let’s celebrate the woman who discovered the BRCA1 gene.

Before 1990, breast cancer was seen as a roll of the dice.

Most doctors believed it was caused by the environment, lifestyle, or just bad luck.

The idea that it could run in families because of a single faulty gene was considered fringe science.

Until Mary-Claire King came along.

For 16 years, she tracked families, analyzed blood samples, and studied genetic patterns.

And her research confirmed that a single gene on chromosome 17 dramatically increased a woman’s risk of developing breast and ovarian cancer.

She named it BRCA1.

And it changed how millions of women understand their risk.

It opened the door to genetic testing, early detection, and life-saving prevention.

And October, Breast Cancer Awareness Month, is the perfect time to thank the woman who made hereditary breast cancer something we can see, test for, and act on.

But King’s story doesn’t stop there…

In the 1980s, she took her genetics expertise to Argentina, where a brutal military dictatorship had abducted children from imprisoned mothers.

Those babies were illegally adopted by military families and lost to their relatives forever.

Unless someone could prove who they really were.

King developed a method using mitochondrial DNA to match children to their biological families through maternal lineage.

Her work reunited 138 families and established the scientific foundation for modern forensic DNA work used by the UN, human rights organizations, and military labs around the world.