Ian Wilmut Biography

World of Genetics on Ian Wilmut

Ian Wilmut and his associates were the first to clone a mammal from the fully differentiated cells of an adult animal, and thus, thrust the practical concepts and ethics of cloning into scientific and public debate.

Wilmut was born in Hampton Lucey, Warwick, England. He attended the University of Nottingham, where he became fascinated with embryology after meeting G. Eric Lamming, a world-renowned expert in reproduction. The meeting became a turning point for Wilmut, who set out on a singular quest--to understand the genetic engineering of animals. Wilmut graduated from Nottingham in 1967, with a degree in agricultural science.

Wilmut continued his studies at Darwin College at Cambridge University in England. There he received his doctoral degree in 1973, awarded after he completed his thesis on the techniques for freezing boar semen. Wilmut immediately took a position at the Animal Breeding Research Station, an animal research institute supported by government and private funds. The research station eventually became the Roslin Institute. It is headquartered in Roslin, near Edinburgh, Scotland.

In 1973, after receiving his doctorate, Wilmut produced the first calf ("Frosty") born from a frozen embryo that had been implanted into a surrogate mother. The motivation for such an experiment was to harvest cows that provide the best meat and milk by implanting their embryos into other females. The average cow can birth five to ten calves during their lifespan. With the ability to transfer embryos, cattle breeders could increase the quality of their animal stock.

Wilmut continued his research during the 1980s, despite other scientists' growing discouragement in the possibility of cloning. In 1996, Wilmut overheard a story in an Irish bar, while attending a scientific meeting, that solidified his interest in cloning. The story concerned a researcher in Texas who had cloned a lamb using a differentiated cell from an already developing embryo.

Like a fertilized egg that contains enough deoxyribonucleic acid (DNA) to build an entire organism, a differentiated cell carries a full complement of the genetic material for DNA, which forms a blueprint for an animal's characteristics. To clone an animal, an adult animal cell would have to be harvested, and the nucleus placed in an embryo cell, thereby replacing the nucleus of the embryo cell. The problem Wilmut considered was how to get the new nucleus to spawn growth in the embryo cell.

Keith Campbell, a biologist at the Roslin Institute, had an insight that proved to be crucial. Campbell deduced that an egg probably will not use genetic material from a transplanted adult cell because the cycles of each cell are not synchronized. Cells go through specific cycles, growing and dividing and making an entirely new package of chromosomes each time. In order to synchronize the cells, Campbell slowed down adult mammal cells--in fact, nearly stopping them--so they would actually exist in synchrony with the embryos. Then each embryo could be joined with an adult cell, and in turn, they could join together and grow. To slow an already developing or adult cell down, Campbell forced it into a hibernating state by depriving it of nutrients. With this method, Campbell and Wilmut were able to clone two sheep from developing embryo cells. They named the sheep Megan and Morag.

To clone an adult sheep, Wilmut and Campbell harvested udder, or mammary, cells from a six-year-old ewe. The cells were preserved in test tubes and starved by reducing their serum concentration for five days. Out of 277 attempts, 29 embryos survived to the stage where implantation was possible. The two scientists implanted an embryo when it was six days old into a surrogate mother, and on July 5, 1996, Dolly (named after country singer Dolly Parton) was born. In late November 1997, Dolly was successfully mated with a four-year-old Welsh Mountain ram (David) and her lamb (Bonnie) was born on the morning of April 13, 1998. The birth of the lamb confirmed that while Dolly's embryonic origins were unique, she was able to breed normally and produce a healthy offspring.

Wilmut remains passionate about his work, asserting the necessity of animal cloning research, and its eventual applications for medicine.

Recent Updates

February 8, 2005: Wilmut and two colleagues received a one-year research license from the Human Fertilisation and Embryology Authority, the United Kingdom's regulatory body that oversees human embryo research, to extract stem cells from cloned human embryos. The purpose of his research is to investigate motor neuron disease (MND). Wilmut and his colleagues will take cells from patients with MND and create cloned embryos using a technique called cell nuclear replacement. The embryos thus created will divide and produce stem cells. The stem cells will then be coaxed to become neurons and these neurons will be compared with neurons from people who do not have MND in the hopes of increasing scientists' understanding of why motor neurons degenerate. Although the approval of this research has drawn criticism from pro-life groups, Wilmut points out, "This is not reproductive cloning. The eggs we use will not be allowed to grow beyond 14 days." Source: New Scientist, www.newscientist.com, February 8, 2005.