Originally published by Farmers Guardian

By Alistair Driver

SCIENTISTS at the University of Bristol claim to have discovered a previously unknown route by which GM genes may escape into the natural environment.

They have identified a natural process they say that would allow synthetic genes to move across GM organisms and out into the wild.

The team of scientists wanted to establish whether a process applied in laboratories to manipulate genes could occur naturally in the wild.

The process involves the bacterium Agrobacterium tumefaciens, which ‘transforms’ plant tissue at ‘plant wound’ sites.

Scientists at Bristol’s School of Biological Sciences had already used the bacterium to genetically manipulate fungi. The transformation process is stimulated by a hormone, acetosyringone, which is released by wounded plants and allows ‘foreign genes’ to modify cells.

Agrobacterium and fungi are likely encounter each other at plant wound sites, where acetosyringone is present, in the natural environment.

Professor Gary Foster and colleagues at Bristol University tested whether natural gene transfer from bacterium to fungus can occur in nature on plants.

Prof Foster said their results ‘clearly demonstrate that when placed together on damaged plant tissue, Agrobacterium readily transforms associated fungi’.

“This suggests a previously unknown route for horizontal gene transfer in nature,” said Prof Foster

He said these results could have implications for the risk assessment of GM plants generated with the help of the Agrobacterium, which can survive within plant tissue following artificial transformation in tissue culture.

This research shows that these bacteria have the potential to move the same genetic modifications to fungi in a natural environment, Prof Foster said.

“This study suggests that the encounter between Agrobacterium and a fungus on the plant surface may lead to gene flow in a previously overlooked way, potentially leaking GM genes into the natural world,” he said.

He said the work showed that scientists must ensure the Agrobacterium is eliminated prior to the release of GM plants in which it has been used.

The Bristol study, published online in PLoS ONE, was carried out with financial support from Natural Environment Research Council.