FRENCH researchers have claimed that a large proportion of scientific studies on genetically modified crops have been tainted by conflicts of interest, either because an employee of a GM-producing company is one of the authors or the study received funding from a biotech company.

Out of the 579 published studies on GM crops that were analysed by researchers affiliated to France's National Institute for Agricultural Research, about 40% showed such conflict of interest.

"We found that ties between researchers and the GM crop industry were common," said the study, which also found that studies with such conflicts of interest had a much higher likelihood of presenting a favourable outcome for GM crops, compared to studies with no GM sector input.

"In particular, we found that, compared to the absence of COI (conflict of interest), the presence of a COI was associated with a 50% higher frequency of outcomes favorable to the interests of the GM crop company," the study concluded.

Common crops like corn and soybean can be made resistant to certain pests by introducing genes from a bacteria called Bacillus thuringiensis, hence the prefix 'Bt' on several pest-resistant GM varieties. Considerable research has been devoted to charting yhe efficacy and durability of Bt crops.

Thomas Guillemaud, director of research at France's National Institute, told AFP that the team originally looked at 672 studies before narrowing down to the pool to 579 that showed clearly whether there was or was not a financial conflict of interest.

"Of this total, 404 were American studies and 83 were Chinese," he said. "The most important point was how we also showed there is a statistical link between the presence of conflicts of interest and a study that comes to a favourable conclusion for GMO crops. We thought we would find conflicts of interest, but we did not think we would find so many," noted Mr Guillemaud.

One limitation of the study was that it investigated only direct financial conflict of interest because, as the researchers point out: "Authors may have affiliations to GM crop companies of other types, such as being members of advisory boards, consultants, or co-holders of patents, and this could also have a significant impact on the outcomes of studies on GM crops."