Emma Young

Pigs implanted with spinach genes have been created by Japanese scientists, according to unconfirmed local newspaper reports. The team claims it is the first to successfully insert a plant gene into an animal.

The pigs reportedly contain a gene called FAD2, which converts saturated fat into an unsaturated fat called linoleic acid. Akira Iritani, at Kinki University in western Japan, who led the research, says the genetically modified pigs contain 20 per cent less saturated fat than normal pigs - and so could be healthier to eat.

"I know genetically-modified food has met with poor public acceptance, but I hope safety tests will be conducted to make people feel like eating the pork for the sake of their health," said Iritani.

The pigs were born three and a half years ago. Iritani says he wanted to be sure the genetic modification would be passed down through offspring before revealing details of his work. To date, the modification has been confirmed in three generations of pigs and seven generations of mice, he says.

Animal health groups in the UK have been quick to condemn Iritani's work. "We are absolutely staggered by the reports of this research," said Vicky Robinson of the UK's Royal Society for the Prevention of Cruelty to Animals. "It is totally disgraceful."

However, Iritani is yet to publish his research, and numerous animal biotechnology experts contacted by New Scientist say they have had no previous hint of the experiments.

Iritani has been researching pig biology for over 20 years. He is also known as the leader of a maverick team hoping to isolate and clone mammoth DNA.