Scientist bombarded with requests to clone dead people
Contrary to popular belief, Dolly the Sheep was not actually the first animal to be cloned.
But the reason was she was so famous is probably because she was the first mammal to be cloned from an adult cell.
She’s the subject of a documentary which airs on Wednesday on BBC Two, called Dolly: The Sheep that Changed the World.
Dolly was created in 1996 at the Roslin Institute in Midlothian, by a team led by Professor Ian Wilmut, as part of their research to find treatments for genetic disorders.
It was a controversial lab, with animal rights campaigners pointing out that genetically modifying animals and using them for scientific gain was causing them immense suffering.
Two fires broke out in separate animal research centres on the same day – with fire chiefs warning it might have been the work of activists.
Professor Ian Wilmut of the Roslin Institute with Dolly the Sheep
Dolly was the only surviving lamb from 277 cloning attempts and was created from an udder cell taken from a six-year-old Finn Dorset sheep.
The pioneering technique the Roslin team used involved transferring the nucleus of an adult cell into an unfertilised egg cell whose own nucleus had been removed.
An electric shock stimulated the hybrid cell to begin dividing and generate an embryo which was then implanted into the womb of a surrogate mother.
The result was a newborn animal that was a genetic copy of the original cell donor.
She was named after country singer Dolly Parton, with Wilmut explaining at the time: “Dolly is derived from a mammary gland cell and we couldn’t think of a more impressive pair of glands than Dolly Parton’s.”
Dolly was created in 1996 and lived until she was six – half her usual lifespan
It was an “off the cuff” joke – but the name stuck.
As the news of Dolly’s successful creation spread, scientists at the lab were bombarded by requests from grieving people, desperate for their loved ones to be cloned and brought back from the dead.
Dr Ron James, former managing director of PPL Therapeutics, the firm that helped make Dolly, said: “We had a letter which said that a chap’s girlfriend had died a couple of weeks before he was due to get married, and could we clone her?
“The answer is, theoretically it might be possible, but you’re going to get a tiny baby that’s going to be 18 or 20 years younger than your girlfriend was.”
It would also potentially take hundreds of embryos to get one successful human clone, all of which would need to be carried by a surrogate who would know it was unlikely they would be able to carry to term.
Dolly was bred with a Welsh Mountain ram and produced six lambs in total – Bonnie, twins Sally and Rosie, and triplets Lucy, Darcy and Cotton.
Dolly Parton was the special sheep’s namesake after a joke nickname stuck
But in late 2001, at the age of four, she developed arthritis and began to walk stiffly.
This was treated with anti-inflammatory drugs at first, but eventually Dolly was euthanised aged six when she also developed lung disease – living just half her expected lifespan.
It was commonly thought that the disease was due to her being cloned, but actually Roslin scientists insisted this wasn’t the case – it was fairly common in sheep and other sheep in the same flock had died from the same affliction.
However, it particularly affects sheep who are kept indoors – and mega-star Dolly always slept indoors for security reasons.
After her death, Dolly’s body was preserved via taxidermy and is currently on display at the National Museum of Scotland in Edinburgh.
Despite sensational speculation about human cloning at the time of her birth, Dolly’s most important legacy was a massive boost to stem cell research.
The same cell reprogramming technique used to create Dolly was adopted by other scientists to generate “induced pluripotent stem cells” (iPS cells) from adult human skin cells.
Like stem cells plucked from early stage embryos, iPS cells have the potential to transform into any kind of tissue in the body, raising the possibility of ethically-approved stem cell therapies tailored to suit individual patients.