The American chestnut tree is on the brink of a genetically engineered comeback. Evidence, not fear, must decide the US public debate
FOUR billion magnificent trees. One deadly Asian fungus. That was around a century ago. By the 1950s, the fungus had won, almost completely wiping out the American chestnut, an iconic species loved by the public.
The disease also deprived the US of a quarter of its native hardwood, a rot-resistant material used to make log cabins, posts, poles, flooring and railroad sleepers. Gone, too, were the edible chestnuts that once roasted on an open fire.
Now, however, the American chestnut is on the brink of a comeback, thanks to a 20-year genetic engineering project. By adding a single gene from wheat, researchers have created fungus-resistant trees that pass their resistance on to their offspring and, hopefully, subsequent generations too (see "American chestnut set for genetically modified revival"). Modified strains that are even more resistant are not far behind.
The project is the first to use genetic modification to rescue a threatened species from oblivion. Since 2006, more than 1000 modified chestnut trees have been planted in contained plots, and now the researchers are preparing to apply to plant them in the wild. For this, they will need to get permission from the US Environmental Protection Agency and Department of Agriculture. And because chestnuts are edible, they will also need to convince the Food and Drug Administration that they are safe to eat.
If all goes to plan, in around 20 years the American chestnut will have reclaimed its former glories. But the project is maturing at a time when US public opposition to GM is on the rise. Vermont has become the first state to require mandatory labelling of GM food; similar legislation is being considered in 29 other states.
This is partly down to a general desire for transparency, but it is also due to the rise of radical anti-GM activists, who have begun using tactics similar to those that helped destroy the prospects for GM technologies in Europe 20 years ago: chiefly, sowing doubt in the minds of the general public.
Against this background, it will be worth watching the reaction to the modified chestnuts closely. Die-hard anti-GM campaigners are unlikely to hold back, given their resistance to projects that might help feed the world or improve global health.
Will the US public at large share their hostility? Hopefully they will instead appreciate the potential that biotechnologies hold for conservation efforts – albeit in ways that may take some getting used to – and permit a balanced, evidence-based debate.
It may turn out that modified chestnuts pose an unacceptable risk, though it is hard to envisage how that could arise. It might also be that any sort of high-tech intervention in the "untouched wilderness", GM or otherwise, is considered less appealing than letting nature take its course – even if that means decline. In that case, a rival project using conventional means to breed resistance – although it will be weaker than the GM variety –may be a more acceptable compromise.
Given the tensions at play, the project will be a critical test of public opinion over whether GM has a place in conservation. Right now, you wouldn't bet on it. But it is a question that deserves to be debated properly: the fate of a species should not be determined by fear and prejudice.
This article appeared in print under the headline "GM nuts on the horizon"