Lederberg, Joshua (1925- )

US geneticist who was awarded the Nobel Prize for Physiology or Medicine in 1958 for work on genetic recombination and the organization of bacterial genetic material. He showed that bacteria can reproduce sexually, combining genetic material so that offspring possess characteristics of both parent organisms. He shared the prize with George Beadle and Edward Tatum.

Lederberg is a pioneer of genetic engineering, a science that relies on the possibility of artificially shuffling genes from cell to cell. He realized in 1952 that bacteriophages, viruses which invade bacteria, can transfer genes from one bacterium to another, a discovery that led to the deliberate insertion by scientists of foreign genes into bacterial cells.

Lederberg was born in New Jersey and studied at Columbia and at Yale, where he worked with Tatum. He was at the University of Wisconsin 1947-59, rising to professor, and moved in 1959 to Stanford University, California, becoming director of the Kennedy Laboratories of Molecular Medicine in 1962.