Tuesday, November 24, 1998 Published at 00:40 GMT
Jumping genes are nature's casanovas
Gene research into bananas has borne fruit
By Toby Murcott of BBC Science
New research has shown that a specific gene can jump between totally different plants with remarkable promiscuity.
The big puzzle is just how these genes have jumped so successfully between species.
There are known mechanisms for this type of transfer, but the scale of the movement has astonished the researchers, who report their findings in the US scientific journal, the Proceedings of the National Academy of Sciences.
The appearance of these genes in plants as diverse as banana, coffee, cucumber and rubber tree, points to a much greater tendency for plants to swap genetic material than previously thought.
The way they do it is to make a protein which acts like chemical scissors, snipping the gene out of one length of DNA and cutting itself a hole in the next.
Nothing to fear
Even though the transfers occurred over a period of 10 million years, in evolutionary terms this represents an orgy of promiscuous genetic transfer.
It will, however, raise concerns that "foreign" genes engineered into novel crops may also use the same process to jump from species to species. But the researchers say the timescales involved should mean there is nothing to fear.
Nevertheless, this discovery shows that our understanding of plant genetics is far from complete. Inevitably, it will continue the debate on the safety of genetically engineered food.