Getting to meet Dolly the ovine disrupter

Otago Daily Times

4 days ago

Sheep have always been important to my family.
Having a miserly Glaswegian father meant that with no electric heating or even fires during the winter, we bundled up in hand-knitted woolly jumpers. We devoured legs of lamb, hunks of hogget, shoulders of mutton and more.
We listened in avid silence to Dad as he recounted gory tales of working at Burnside freezing works, gasping and shuddering as he described sneaking home bloody packets of offal to consume later. All of this sounds rather macabre, I know, but we were a typical New Zealand family, well-acquainted with the brutalities of farm life and blue-collar jobs.
My first pet was a little lamb, aptly named Frisky. I loved him very much, as did all my brothers and sisters. Frisky was hilarious. I think he thought he was a human.
He jumped and capered about, sneaking into the house to play hide-and-seek with us, always leaping into our laps for a cuddle and a special treat.
When he died prematurely (of internal bleeding, after my father unwisely decided to tether him with a metal chain one night), we were absolutely devastated. I was seven-years-old and this was my first real encounter with death.
Over the years, my family has continued to foster lambs from local farmers, caring for the little beasts whose mothers have passed or unaccountably rejected them. We've had many fluffy little creatures join our family: Bunty (a ridiculously shy boy who hid in the bushes), Caspian (a fragile black lamb who needed extra love and attention) and Rupert (who grew to be enormous) to name a few.
I've also had the unique pleasure of meeting the world's most famous sheep — Dolly.
Of course, I never had the good fortune to meet Dolly while she was alive (she died in 2003), but I've met her taxidermied self in the National Museum of Scotland.
Dolly was born on July 5, 1996, in a concrete barn on the outskirts of Edinburgh. In all respects, Dolly looked like a perfectly ordinary sheep, but of course she was extraordinary.
Dolly did not arise from natural copulation between two woolly parents, nor even standard laboratory fertilisation. In fact, she arguably had three mothers: one provided the egg, another provided the DNA, and a surrogate third, who carried the cloned embryo to term.
Dolly was cloned by Dr Keith Campbell, Dr Ian Wilmut and colleagues at the Roslin Institute at the University of Edinburgh. The funding for this project was provided by PPL Therapeutics and the Ministry of Agriculture.
Dolly was the product of a process called "somatic cell nuclear transfer". Essentially, Dr Wilmut and his team carefully extracted the nucleus from a cell in the udder of a six-year-old Finn Dorset ewe. They then inserted this nucleus into an egg cell from a different sheep, whose own nucleus had been removed. This hybrid egg was then stimulated to spark cell division and implanted into a surrogate mother — a Scottish Blackface sheep.
One of the early clues that Dolly was a clone came from her white face; she would have had a black face had she inherited her genes from the surrogate mother.
What made Dolly so special?
Contrary to popular belief, she was not the first cloned animal, but she was the first cloned from an adult, fully specialised cell. Earlier cloning experiments used embryonic stem cells that were still flexible in function.
Dolly, in contrast, was created from a mammary gland cell, a type long thought to be permanently fixed in its role. Her creation proved that even a mature cell retains the entire genetic code necessary to generate a complete organism. Dolly's existence challenged decades of scientific assumption and showed that adult cells could be reprogrammed.
Regarding her name, Dr Wilmut explained, "Dolly is derived from a mammary gland cell and we couldn't think of a more impressive pair of glands than Dolly Parton's". I wonder what Dolly Parton thinks of that.
Dolly's existence was kept hidden until the Roslin Institute published its research paper on February 22 1997. A media frenzy was sparked and the world's press descended on Roslin to meet Dolly. I wonder what she made of all the flashing bulbs, microphones, and jostling camera crews.
Media coverage swung wildly from triumphalist predictions of cures for every disease to dystopian fears of designer babies and human clones. A placid Finn Dorset ewe had become an icon of late-20th century science.
Dolly spent her life living in a flock of sheep at the Roslin Institute, a quiet expanse on the outskirts of Edinburgh. I've been out there, for a job interview — which was unsuccessful, as it happens — and can attest to its serene, pastoral setting.
Dolly had six lambs (Bonny, Sally, Rosie, Lucy, Darcy, and Cotton) with a Welsh Mountain sheep named David. By the autumn of 2001, Dolly was beginning to show signs of arthritis, which fuelled the suspicion that cloned animals were destined to age prematurely.
Daily anti-inflammatory treatments helped, but ultimately Dolly had to be euthanised on February 14 2003 at the age of six after being diagnosed with progressive lung disease and severe arthritis. A CT scan had revealed tumours in her chest consistent with ovine pulmonary adenomatosis (OPA), an incurable lung cancer.
Dolly's death was due to a Jaagsiekte sheep retrovirus, a common viral disease in sheep; there is no conclusive evidence that cloning itself caused her illness or shortened her life. Her body was donated to the National Museum of Scotland, where she remains one of its most popular exhibits.
Dolly became part of cultural folklore, immortalised in museums, children's books, bioethics debates and satirical cartoons. Meanwhile, cloning technology quietly advanced.
Since Dolly, scientists have successfully cloned a range of mammals, including pigs, deer, horses, bulls and endangered species like the mouflon and banteng. Efforts are under way to revive extinct animals like the woolly mammoth. Success rates in cloning have dramatically improved; early cloning was notoriously inefficient — Dolly being the sole success out of 277 attempts.
The cloning of primates was achieved in 2018 using the same method which produced Dolly. Gene-edited monkey clones soon followed.
Parallel to these developments, stem cell research has surged forward, allowing ordinary cells to be reprogrammed into pluripotent stem cells capable of regenerating tissues, offering new hope for treating complex diseases. Reproductive human cloning remains globally prohibited or tightly restricted, although therapeutic cloning for research purposes is allowed in a few countries under strict ethical oversight.
Dolly had such a pleasant, good-natured face. In photographs, it almost looks like she is smiling placidly at the camera in a self-satisfied way.
She looks like an entirely ordinary sheep, one who grazed, gave birth, and dealt with illness. And she was, in some respects. But she was born from a question: can life be replicated?
And Dolly leaves us with a bigger question: what happens when life is replicated and what does it portend?
I quite like the fact that something as simple and humble as a mere sheep could disrupt centuries-old notions of life, soul, identity and the sacredness of origin.
• Jean Balchin is an ODT columnist who has started a new life in Edinburgh.