- The British company that helped to create
Dolly, the cloned sheep, has now used the same method to create a calf.
- PPL Therapeutics said the healthy 98lb
animal, called Mr Jefferson, was produced by its American subsidiary in
Blacksburg, Virginia, and delivered at Maryland College of Veterinary Medicine.
- PPL has established itself as a world
leader in the "transgenic" production of human proteins in the
milk of livestock.
- While Mr Jefferson is not transgenic,
the company said the animal's birth opened the way to producing transgenic
cows, whose milk could eventually be used to treat diseases in humans.
- One of PPL's products, used to treat
cystic fibrosis, is already undergoing clinical trials.
- The chief operating officer at PPL, Dr
Julian Cooper, said: "This is an incredibly important development.
- "The technique used was similar
to that used to produce Dolly and the world's first cloned transgenic lamb,
- "While the calf is not transgenic,
we have shown we can do the difficult part, and this success now opens
the way to producing transgenic cows using nuclear transfer, Polly having
proved the principle."
- Foetus cell
- Mr Jefferson was named in honour of his
birth on February 16 - President's Day in the United States.
- The animal was produced using technology
based on that used to clone Dolly and Polly, but whereas Dolly was cloned
from an adult cell, the calf was cloned from the cell off a foetus.
- In response to media speculation over
the origins of Dolly the sheep and claims that it might not be a genuine
clone, the company said: "PPL is confident that Dolly was produced
from an adult mammary cell."
- The managing director of PPL, Dr Ron
James, said: "It would be a shame if the birth of Mr Jefferson, which
is an important step forward for PPL, were to become overshadowed by the
current controversy over Dolly's origin.
- "We have demonstrated we can do
this with the birth of Polly, and Mr Jefferson shows we have the capability
to extend the technique to cattle."