Frozen: The story of Frostie the calf

Frostie calf CROPIan Wilmut is best known for his involvement with the team which cloned Dolly the sheep in 1996. However, his scientific career, which spans more than five decades, includes a variety of groundbreaking achievements and discoveries, which are being revealed as his papers are catalogued as part of the continuing ‘Towards Dolly’ and ‘The Making of Dolly’ projects.

Ian Wilmut initially wished to work as a farmer, but he ‘shuffled sideways into scientific research’*, as he puts it, and ultimately won a scholarship as an undergraduate at Nottingham University to work for two months under Chris Polge at  the Animal Research Station in Cambridge. His role was to help out generally with experiments, but he soon became fascinated by embryos, and returned to work with Polge once he graduated. Wilmut’s PhD, awarded in 1971, was on the freezing of boar semen. Copies of Wilmut’s published papers exist in the archive from 1969 onwards, and a glance through the papers which appeared over the next decade reveal Wilmut’s wide-ranging research on the effects of freezing, thawing and warming on embryos and spermatozoa in mice, sheep and cattle.

In 1973, Wilmut was the first scientist to successfully freeze a calf embryo (using liquid nitrogen), thaw it, and transfer it to a surrogate mother. This process led to the birth of a healthy red and white Hereford-Friesian cross calf, which Wilmut wryly named ‘Frostie’. Wilmut’s findings were published within a few weeks of Frostie’s birth in The Veterinary Record as ‘Experiments on the low-temperature preservation of cow embryos’ (June 30 1973, 686-690), and a copy of the reprint survives in the archives. Wilmut has remarked that this was ‘one of the fastest scientific publications ever’. It also led to some considerable interest from the world’s media, with Wilmut appearing on television and newspapers from as far away as New Zealand seizing upon the story. This media attention was a precursor to the storm which Wilmut, Keith Campbell and team would generate two decades later when Dolly the sheep was born. Wilmut’s discovery of the viability of frozen embryos to produce healthy offspring has since been used across many different species in agriculture and also for the conservation of rare breeds. The first human to be born from a frozen embryo was Zoe Leyland, born in Melbourne in 1984.

Wilmut’s work with Chris Polge equipped him with many of the techniques in reproductive physiology which would instruct his later work on cloning, nuclear transfer, stem cell and regenerative medicine in Edinburgh, where Wilmut moved in 1973. Throughout his career Wilmut has been inspired by the possibilities of advances in reproductive physiology and biotechnology for fertility treatments,practical applications to the farming industry and breakthroughs in treatments or cures for debilitating genetic diseases.

*All quotes taken from The Second Creation: the age of biological control by the scientists who cloned Dolly, I. Wilmut. K. Campbell and C. Tudge (London, 2000).
Clare Button
Project Archivist

Dollymania – Seven Days that Shook the World

Dolly the sheep

1997 was quite a significant year for the Roslin Institute with “’Dolly, the sheep, ‘…the first mammal cloned from a cell from an adult animal…generated an amazing amount of interest from the world’s media.” (Griffin, Harry. ‘Dollymania’, University of Edinburgh Journal, XXXVIII: 2, December 1997, GB237 Coll-1362/4/1476). And so, it’s been exciting to find articles in the offprints discussing her and the issues of cloning, biotechnology, ethics – Dr. Grahame Bulfield even wrote a report to Parliament on what this breakthrough means for science!

Harry Griffin, former Assistant Director (Science) at the Roslin Institute in 1997’s article, ‘Dollymania’ (cited above) provides an insider’s point of view of how Dolly was produced and the science and research involved. He writes,

Dolly was produced from cells that had been taken from the udder of a 6-year old Finn Dorset ewe and cultured for several weeks in the laboratory. Individual cells were then fused with unfertilised eggs from which the genetic material had been removed and 29 of these ‘reconstructed’ eggs – each now with a diploid nucleus from the adult animal – were implanted in surrogate Blackface ewes. One gave rise to a live lamb, Dolly, some 148 days later. Other cloned lambs were derived in the same way by nuclear transfer from cells taken from embryonic and foetal tissue.

On Monday, Dolly provided the lead story in most of the papers and Roslin Institute was besieged by reporters and TV crews from all over the world…. Dolly rapidly became the most photographed sheep of all time and was invited to appear on a chat show in the US. Astrologers asked for her date of birth and PPL’s share price rose sharply. President Bill Clinton called on his bioethics’ commission to report on the ethical implications within 90 days and Ian Wilmut was invited to testify to both the UK House of Commons and the US Congress…. Dolly Parton sad she was ‘honoured’ that we have named our progeny after her and that there is no such thing as ‘baaaaaed publicity’. Sadly, we also received a handful of requests to resurrect relatives and loved pets.

IMG_4284In the article, ‘Seven days that shook the world’ by Harry Griffin and Ian Wilmut in New Scientist, 22 March 1997 also describe the reality of the science of cloning in the face of intense media speculation and reportage.

Dr. Grahame Bulfield, former Director of the Roslin Institute, wrote several articles in 1997 on biotechnology, ethics, livestock and cloning. In some articles, he writes generally on the techniques of genetic engineering, genome analysis, and embryo manipulations and provides a biological context of these new technologies. (GB237 Coll-1362/4/1394 – 1400). He discusses Dolly more directly in the article, ‘Dit is pas het begin’ in the Dutch journal Natuur & Techniek, No. 8, 1997 (4/1376) IMG_4266and The Roslin Institute and Cloning an address to the Parliamentary and Scientific Committee in Science in Parliament, Vol. 54, No. 5, September/October 1997 (4/1400). In this particular article he writes specifically about Dolly:

As you know we have been thrown into the middle of public debate recently with a considerable amount of public interest and concern about “Dolly”. IMG_4275Over a period of about five days we had 3,000 telephone calls, 17 TV crews and we basically ground to a halt. We are perfectly aware now of the issues that are raised , and I don’t believe that a scientific organisation like ours can do anything buy try and be proactive in terms of communicating new biotechnology advances to the public and Government and ensuring the issues involved are widely debated.