Friday, April 9, 1999 Published at 11:11 GMT 12:11 UK
Multiple monkey cloning attempt
Cloning sets of rhesus monkeys could make the technology suitable for humans
An intense effort to clone a set of monkeys for medical research is under way in the USA.
She said having cloned monkeys would allow new drugs and vaccines to be tested on sets of genetically-identical animals. If successful, cloning technology will have moved a step nearer to being safely applied to humans.
Treatments for Aids and some cancers could benefit, as any differences between the test animals and the controls could only be the result of the treatments.
"The medical community is just desperate for this kind of animal," said Dominko, speaking to Reuters at a cloning seminar in Argentina.
"Disturbing questions raised"
The project was attacked by Dr Donald Bruce, director of the Church of Scotland's Society, Religion and Technology Project.
He told BBC News Online: "If they were successful in doing this, that would be one more step towards cloning human beings."
"Cloning primates as laboratory animals also raises other rather disturbing questions, partly because of their similarity to humans," he said.
"One would have to know what the very special reason was for doing this rather than saying 'wouldn't this be a useful generic tool'. That reduces animals to being mere instruments."
Hit and miss
There are significant technical difficulties however. The first cloned mammal, the sheep Dolly, was produced in 1996 at the Roslin Institute in Scotland, but only after extensive work. Over 400 unfertilised eggs, 29 embryos and 13 surrogate mothers were used before the eventual success.
The problem in cloning monkeys is that whilst sheep and cow eggs cost around 10 pence, a rhesus monkey egg costs £190. The nuclear transfer cloning process requires the DNA from the nucleus of an adult cell to be placed into an egg, which has had its nucleus removed.
"If you're working with sheep or cattle, you have literally thousands of eggs available from slaughterhouses or farms that support thousands and thousands of animals that you can use in experimentation," Dominko said.
She admitted it may be a number of years before they successfully clone the monkeys, despite a narrow failure three years ago.
Two monkeys were born after 166 nuclear transfer attempts but were not identical as the nuclei came from different sources. Also, the cells used were taken from embryos, not adults.
At the time, Dominko's colleague, Don Wolf said: "If we can do this in monkeys, most people will see the significance of that to humans."
Researchers are particularly interested in primates as laboratory animals because they are closely related to humans.
Rhesus monkeys are not an endangered species and their reproductive organs function almost identically to those of humans. Female rhesus monkeys even have a menstrual cycle the same length as that of humans.
This similarity, and the similar scarcity of eggs, would mean that any cloning technique developed successfully in rhesus monkeys would likely be applicable to humans. One reason experts have argued that human cloning should not take place is because the technology was far too unreliable.