1960s John Gurdon, a British biologist, produces the first clones of animals from the skin cells of frogs, but the tadpoles do not develop into adults and no one is able to reproduce the work on higher mammals.
1978 The film Boys from Brazil is released, depicting the cloning of Adolf Hitler in the jungles of South America by fanatical ex-Nazis.
1978 Karl Illmensee, a scientist at the University of Geneva, claims to have cloned mice, but the research is disputed amid accusations of scientific misconduct.
1986 Steed Willadsen, a brilliant Danish scientist, publishes research proving that it is possible to clone sheep from early embryos.
1996 Ian Wilmut and colleagues at the Roslin Institute in Edinburgh clone sheep using the technique of nuclear transfer, but only using early embryo cells.
1997 Wilmut announces the creation of Dolly, the first adult clone of an animal, generated by transferring the nucleus of an udder cell taken from a six-year-old sheep into an unfertilised egg cell which had his own nucleus removed.
1998 Scientists at Hawaii University prove the Dolly result was not a fluke by cloning several generations of mice.Reuse content