Mary-Claire King

Mary-Claire King grew up in Wilmette, Illinois, and lost her closest childhood friend to kidney cancer at 15, a death she later said pushed her toward science. She studied mathematics at Carleton College, graduating in 1967, then went to Berkeley intending a career in statistics before a summer working in Chile's land-reform program and a doctoral advisor, Allan Wilson, redirected her into genetics. Her 1973 dissertation used protein comparisons to show that humans and chimpanzees share about 99 percent of their genetic material, a finding that startled a field still debating how closely related the species were, and set the pattern she would repeat: using genetics to answer a question other methods could not settle.

King spent the 1970s and 1980s pursuing an idea most geneticists considered a long shot, that a single gene could explain a meaningful share of inherited breast cancer, mapping affected families over more than a decade of unfunded, unfashionable work. In 1990 she located the gene to a region of chromosome 17, naming it BRCA1 before it was even cloned, a discovery that opened genetic testing and risk-based prevention for breast and ovarian cancer. Starting in 1984 she took the same techniques into human rights work, developing methods to use mitochondrial DNA to identify children stolen during Argentina's Dirty War, work later extended to identify the disappeared in El Salvador, Chile, Rwanda and the Balkans. She has taught at the University of Washington since 1995.

King pursued the breast-cancer gene for years after most of the genetics establishment had concluded the search was not worth funding, betting a career on a hypothesis colleagues considered outdated single-gene thinking in a field moving toward more complex models; she was right, and the field had to revise its assumptions rather than her. The forensic work carried its own weight: the identifications she made for Argentina's Abuelas de Plaza de Mayo returned kidnapped children, some by then adults with no memory of their birth families, to relatives who had spent years searching, reunions that were as often wrenching as joyful for people who had been raised, sometimes lovingly, by the families of the officers who had killed their parents.

King holds the National Medal of Science and the Lasker~Koshland Special Achievement Award, and continues to run a lab at the University of Washington studying the genetics of schizophrenia and other inherited conditions. Her standing as a scientist is not in dispute; what remains unresolved is a broader argument her career keeps getting cited in, about how much of the genome will ultimately explain complex disease and how far forensic genetics should reach into human rights investigations, questions still being worked out by researchers who cite her BRCA1 paper as the model for how to find an answer nobody yet had at the time.

Mary-Claire King's life against the full span of the corpus — the fading end marks a life still in progress.

• Human-chimpanzee genetic similarity study discovery
  Doctoral research showing the two species share about 99% of their genetic material 1973
• BRCA1 gene locus discovery
  Located the inherited breast- and ovarian-cancer gene to chromosome 17 1990
• Mitochondrial DNA identification method for the Abuelas de Plaza de Mayo discovery
  Identified dozens of children stolen during Argentina's Dirty War 1984
• International forensic human-rights genetics program mission
  Extended identification work to El Salvador, Chile, Rwanda and the Balkans 1991

• February 27, 1946 aged 0 Born in Wilmette, Illinois
• 1967 aged ~21 Graduates Carleton College with a degree in mathematics
• 1973 aged ~27 Earns a Ph.D. in genetics from UC Berkeley, showing humans and chimpanzees share about 99% of their genes
• 1984 aged ~38 Begins applying mitochondrial DNA identification to Argentina's Abuelas de Plaza de Mayo cases
• 1990 aged ~44 Locates the BRCA1 breast-cancer gene to chromosome 17
• 1995 aged ~49 Joins the University of Washington as the American Cancer Society Professor
• 2014 aged ~68 Receives the Lasker~Koshland Special Achievement Award in Medical Science
• 2016 aged ~70 Receives the National Medal of Science

• James Watson 1928–2025
  Co-discoverer of the DNA double helix structure, earning a Nobel Prize in Physiology or Medicine. contemporary in genetics
• Barbara McClintock 1902–1992
  Cytogeneticist who discovered transposable elements and won the Nobel Prize in Physiology or Medicine. predecessor in genetics
• Linus Pauling 1901–1994
  Chemist and peace activist who won two unshared Nobel Prizes in Chemistry and Peace. kindred in science and public conscience
• Rachel Carson 1907–1964
  Marine biologist whose book Silent Spring launched the modern environmental movement. kindred in science and public conscience