London - Scientists who created Dolly the sheep, the world's first cloned mammal, have said she has slight DNA damage which could have an impact on how cloning technology is used in the future.
Dolly and two other cloned sheep have shorter telomeres - the tiny strands of DNA at the end of chromosomes that scientists believe may hold the secrets to youth and ageing. Telomeres shorten each time a cell divides and are progressively eroded as an animal ages. As the telomeres shorten the chromosomes can become unstable and prone to damage.
Researchers from Edinburgh's Roslin Institute and PPL Therapeutics said Dolly, who was cloned from a cell taken from a six-year-old sheep, had telomeres which were about 20 per cent shorter than those of other sheep of a similar age.
The finding, which will be published in today's issue of the science journal Nature, is not unexpected. In Dolly's case, the shortening of telomeres was compounded because she was derived from a cell from a middle-aged animal.
