Mary-Claire King ’67 receives prestigious National Academy of Sciences award
King studied mathematics at Carleton.
The National Academy of Sciences is presenting its 2025 Public Welfare Medal to Mary-Claire King ’67 for her genetic research and its transformative application to human rights. The medal is the Academy’s most prestigious award, presented annually to honor extraordinary use of science for the public good.
King’s use of mitochondrial DNA reunited families who were victims of Argentina’s “Dirty War,” advanced forensic genetics worldwide, and illustrated the power of science in promoting justice and public welfare.
King played a pivotal role in reuniting families torn apart during Argentina’s Dirty War (1976–1983), when the military dictatorship abducted infants from their families, placing them in the households of police, military, and collaborators. The disappeared children’s grandmothers, who became known as the Abuelas de Plaza de Mayo, sought help from geneticists to identify children who they suspected to be among the kidnap victims. In 1983, the grandmothers asked King for help.
With the children’s parents also among the disappeared, determining the biological relationships between grandparents and the missing children required new methods to establish kinship. Developing first a mathematical model — the Index of Grandpaternity — then sequencing mitochondrial DNA (mtDNA), King was able to establish relationships at a high level of certainty through maternal lineages alone. Because mtDNA is inherited exclusively from the mother and remains unchanged except by mutation across generations, King was able to compare the mtDNA sequences of the children with those of potential maternal relatives. For the first several years, all sequencing was by hand, one DNA base-pair at a time. King’s approach has led to the identification and reunification of 138 families so far.
To place the approach on a rigorous legal and scientific footing, King worked with the grandmothers to establish the National Bank of Genetic Data in Argentina, the first institution dedicated to systematically preserving genetic information for future identifications.
King extended her work to the identification of remains, based on matching DNA extracted from teeth to DNA of maternally related survivors. Working with the U.S. armed forces’ Central Identification Laboratory in Hawaii, King identified remains of soldiers listed as MIA from the Vietnam War, the Korean War, and WWII. She has also assisted human rights organizations with genetic identifications on six continents, as her young colleagues from Argentina formed the United Nations Forensic Anthropology Team, which now carries out DNA identifications worldwide using this approach.