Dolly the sheep 'did not have early onset osteoarthritis'

X-rays show that Dolly the Sheep's joint disease was quite normal. Dolly was lame in one knee but the extent of osteoarthritis revealed by the scans was'not unusual for a seven-to-nine-year-old naturally-conceived sheep

New research now shows this wasn't the case. Images of bones 8-year-old Dolly, her naturally born daughter Bonnie, and Megan Moran. Sheep usually live for between 10 and 12 years; Dolly was euthanized before she turned seven, and the bone disease afflicted since she was about five-and-a-half years old.+Around the time of her death, this had led to concerns about early onset of age-related diseases among cloned animals. And in fact, it was soon taken for granted that a outcome of cloning was an early grave.

However, a study a year ago of cloned ewes Debbie, Denise, Dianna and Daisy, who were derived from the cell line that gave rise to Dolly - found evidence of only mild or, in one case, moderate osteoarthritis.

Biologists started to suspect this was the case last year following a study of four eight-year old ewes produced from the same clonal line as Dolly.

It took 277 attempts to clone Dolly, and for a while she was arguably the world's most famous sheep. Mild osteoarthritis had been found in some of the sheep, and only one displayed moderate arthritis.

But the scientists weren't content to stop there.

But X-rays of Dolly's skeleton show that the fear of premature, clone-related ageing appears to have been misplaced, as her joint disease was actually quite normal.

Researchers in Scotland and England based their conclusion on X-rays of Dolly's skeleton, held by National Museums Scotland
Researchers in Scotland and England based their conclusion on X-rays of Dolly's skeleton, held by National Museums Scotland

Tim King, Dolly's vet and now deputy head of the Royal (Dick) School of Veterinary Studies at the University of Edinburgh, said in a statement that the research "is an important contribution to the understanding of how cloning may impact on animal health" because it suggests Dolly's arthritis "was not as a result of cloning". "We therefore felt it necessary to set the record straight".

The only formal record of osteoarthritis in Dolly was a brief mention in a conference abstract, which reported she had osteoarthritis of the left knee. In fact, they state that the osteoarthritis observed in the clones is similar to the osteoarthritis observed in naturally conceived sheep.

"We found that the prevalence and distribution of radiographic osteoarthritis were similar to that observed in naturally conceived sheep, and our healthy aged cloned sheep", said Sandra Corr, professor of small animal orthopaedic surgery at Glasgow University.

'As a result we conclude that the original concerns that cloning had caused early-onset OA in Dolly were unfounded'.

Although Dolly lived most of her life at the Roslin Institute, she is said to have lived a normal life even after she was found to have been infected with a virus that causes lung cancer in sheep.


Related:

Comments

Latest news

Taylor Swift announces 2018 United Kingdom and Ireland tour dates
But subscribers of TaylorSwift.com will be able to get theirs sooner and purchase tickets in advance beginning Wednesday November 29.

Marsh joins Warner on Australia's injury-watch list
But scores of 60 and 64 against South Australia earlier this month couldn't stop Shaun Marsh edging him out for the position. I'm getting a bit of physio treatment at the moment and hopefully it's settled down over the next 24 or 48 hours.

Zaheer Khan and Sagarika Ghatge host a low-key wedding reception
Out-of-favour India spinner Harbhajan Singh who was teammate of Zaheer in the Indian team and also with Mumbai Indians. During the party, Sagarika looked ethereal in pink lahenga-sari and Zaheer looked handsome in black velvet blazer.

Alshon Jeffrey on his former Bears Super Bowl appearance promise
It's time for fans to give some thanks to the 9-1 Philadelphia Eagles . "I guarantee you we'll win the Super Bowl next year ". Then again, statistical milestones don't seem to be what drives Jeffery. "That's all that matters".

Facebook Tests Snapchat's Streak Feature on Messenger
Facebook Messenger's implementation is more open, counting from regular chats and not just visual messaging like Snapchat . Translation: 1 out of every 4 people on the entire planet uses Facebook at least once a month.

Other news