H. Robert Horvitz won the 2002 Nobel Prize in Physiology or Medicine (with Sydney Brenner and John Sulston), for his work on programmed cell death (apoptosis), and for his studies concerning organ development in C. elegans. His apoptosis studies may also improve the understanding of neurological disorders such as amyotrophic lateral sclerosis (ALS), a disease that killed Horvitz's father in 1989. In collaboration with others, Horvitz identified a gene involved in the inherited form of ALS, and he is also pursuing other genes involved in the disease. "My hope is that my discoveries will one day lead to advances in medicine that alleviate human suffering and contribute to the world in ways that will benefit mankind," Horvitz has said.

He is also an investigator for the Howard Hughes Medical Institute and a member of the McGovern Institute for Brain Research at MIT, and a member of the MIT Center for Cancer Research. He holds appointments at the Massachusetts General Hospital in neurology and in medicine.

Horvitz received bachelor's degrees in mathematics and economics from MIT (1968) and an M.A. and Ph.D. (1974) in biology from Harvard University. He was a postdoctoral researcher at the Medical Research Council Laboratory of Molecular Biology in Cambridge, England. He joined the faculty of MIT in 1978 and became professor of biology in 1986 and an investigator of the Howard Hughes Medical Institute in 1988.