Cynthia Jane Kenyon (born February 21, 1954) is an American molecular biologist and biogerontologist known for her genetic dissection of aging in a widely used model organism, the roundworm Caenorhabditis elegans. She is the vice president of aging research at Calico Research Labs, and emeritus professor of biochemistry and biophysics at the University of California, San Francisco (UCSF).

In 1976, Cynthia Kenyon graduated valedictorian in chemistry and biochemistry from the University of Georgia.^{[citation needed]}

In 1981, Kenyon received her Ph.D. from MIT, where, in Graham Walker's laboratory, she looked for genes on the basis of their activity profiles, discovering that DNA-damaging agents activate a battery of DNA repair genes in E. coli.^{[citation needed]}

Kenyon then did^[when?] postdoctoral studies with Nobel laureate Sydney Brenner at the MRC Laboratory of Molecular Biology in Cambridge, England, studying the development of C. elegans.^{[citation needed]}

Since 1986, Kenyon has been at UCSF, where she was the Herbert Boyer Distinguished Professor of Biochemistry and Biophysics and is now an American Cancer Society Professor.

In 1993, Kenyon discovered that a single-gene mutation (Daf-2) could double the lifespan of C. elegans, and that this could be reversed by a second mutation in daf-16m.

In 1999, Kenyon co-founded Elixir Pharmaceuticals with Leonard Guarente to try to discover and develop drugs that would slow down the process that makes people age.

Beginning in November 2013, Kenyon served as a part-time advisor at Calico, a new company focused on health, well-being, and longevity.^{[citation needed]}