Hartwell, Leland H (1939- )

US geneticist who was awarded the Nobel Prize for Physiology or Medicine in 2001, shared with British microbiologists R Timothy Hunt and Paul Nurse, for his discovery of a class of genes that act as regulators in the cell cycle.

Hartwell began studying cell growth mechanisms in budding yeast, a micro-organism used to bake bread and brew beer. He identified a number of genes responsible for cell growth, such as the ‘start’ gene necessary to begin a cell growth cycle. Hartwell also discovered the ‘checkpoint’ gene, responsible for the detection of defects in cell growth, which could halt growth to allow cell repair if a defect was detected.

The genes responsible for yeast cell division have also been found to control cell division in the mammalian cell cycle. In particular, these control genes are closely related to those sites of cell alterations associated with cancer. Hartwell's work can be directly applied to the understanding of the mechanisms involved in cancer cell cycles in humans and may lead to new approaches to the treatment of this disease.

Hartwell was born in Los Angeles, California. He received his PhD from the Massachusetts Institute of Technology in 1964. He became an associate professor of genetics at the University of Washington, Seattle, in 1968 and has held the post of full professor of genetics there since 1973. He joined the faculty of the Fred Hutchinson Cancer Research Center, Seattle, Washington, in 1996 and has been president and director there since 1997. Hartwell was elected as a member of the National Academy of Sciences in 1987.