GM monkeys herald health revolution

Scientists announced a breakthrough that could transform research into a range of incurable diseases but also spark a dramatic increase in the number of monkeys used in experiments.

Researchers have developed a technique to create genetically modified monkeys that suffer from human illnesses.

Experimenting on these monkeys, they believe, will advance our understanding and treatment of incurable conditions such as Parkinson's disease and multiple sclerosis.

But the development has caused consternation among groups opposed to animal experiments because it will almost certainly lead to a leap in the number of primates used in medical research just when there are calls for fewer monkeys to be used.

"It is of high scientific and ethical concern that the creation of transgenic marmosets should be hailed as a success. These experiments will only increase the number of non-human primates subjected to experiments," said Carol Newman of the Dr Hadwen Trust for Humane Research.

It also raises the prospect that we will be able to apply the technique to humans - another primate.

This could help families affected by inherited disorders such as Huntington's disease and cystic fibrosis by permanently eradicating their defective genes from future generations.

The breakthrough was achieved by a team of scientists in Japan led by Erika Sasaki of the Central Institute of Experimental Animals in Kawasaki and Professor Hideyuki Okano of Keio University School of Medicine. Their study, published in the journal Nature, used marmoset monkeys.

The "transgenic" monkeys were created by inserting a gene from a jellyfish into their embryos to make them glow under ultraviolet light - a standard test to see if the technique worked. When the monkeys became adults they passed on this transgenic trait to a subsequent generation of offspring.

This suggests other genes could also be manipulated to create animals that mimic human disorders. This is already possible in mice.

"This is the first case ever established in the world that an introduced gene was successfully inherited to the next generation in primates," Okano said. "Until now, the use of mice and rats has played an important role in life science research of transgenic animals but to conduct research on human illnesses, experiments with primates, animals markedly closer to humans functionally and anatomically than rodents, have become necessary."

The scientists managed to inject the jellyfish gene into 80 marmoset IVF embryos which were transferred into 50 surrogate mothers. Seven animals became pregnant and four of them gave birth to five live babies.

All five offspring were transgenic animals carrying the jellyfish gene, which caused the production of a green fluorescent protein in the skin of the monkeys which made their hands glow under ultraviolet light.

Most importantly, the scientists demonstrated that the jellyfish gene had become incorporated into the reproductive cells of two of the five marmosets - the sperm of a male and the eggs of a female - both of which later produced a second generation of marmosets carrying the transgenic gene.

- INDEPENDENT