Cloning scientists breed 'copy-cat'

The world's first cloned kitten has been produced by scientists.

Researchers in Texas created the cat, named Cc, from a cell taken from an adult tortoiseshell female.

They used the "nuclear transfer" technique pioneered by the Edinburgh scientists who made Dolly the sheep, the first mammal cloned from an adult cell.

Scientists have tried and failed to clone a dog before, but this is thought to be the first time a domestic cat has been cloned.

Mark Westhusin and colleagues from the College of Veterinary Medicine at Texas A&M University fused a cell from one of the adult cat's ovaries with an egg from which the nucleus had been removed.

Genetic material was transferred from the adult cell to the egg, which grew into an embryo and was implanted in a surrogate mother.

Cc, born by Caesarean section on December 22 last year, was "vigorous at birth and appears to be completely normal", the scientists wrote in a paper to be published next week.

Despite being a clone, Cc's coat has a different pattern from that of the donor cat.

"As with other genetically identical animals with multicoloured coats, the cloned kitten's colour patterning is not exactly the same as that of the nuclear donor - this is because the pattern of pigmentation in multi-coloured animals is the result not only of genetic factors but also of developmental factors that are not controlled by genotype," the scientists wrote.

In total 87 cloned embryos were transferred into eight surrogate mothers, resulting in one successful and one failed pregnancy. The research is due to appear in next week's edition of the journal Nature.