With Bayer’s struggle for conquest of Monsanto and the ongoing dispute over the safety of genetic manipulation (GM) of crops dominating the headlines, scientific bodies in the UK and the US have separately come out mostly on the side of GM.

In the UK, the Royal Society has called for the European moratorium on GM crops to be reassessed, saying the science has been misunderstood by the public and misconceived by the EU. It is “inappropriate to ban an entire technology,” said the Society’s president, Professor Venki Ramakrishnan, arguing that products should be assessed on a case-by-case basis.

"GM is simply a technology for introducing a particular set of traits into a plant. And you have to decide on a case-by-case basis which of those traits are appropriate or not," Ramakrishnan told BBC News.

The Royal Society has published a guide meant to answer 18 key questions. It addresses whether GM crops are safe to eat, could harm the environment or produce unexpected side-effects. Saying its intent is to “provide clear, unbiased information on the science of GM crops,” the guide asserts that they are safe, while at the same time acknowledging that cross- breeding with non-GM varieties can produce unintended side-effects.

In a BBC interview, Ramakrishnan acknowledged there were some “legitimate worries,” including the danger that a small number of multinational corporations could monopolize food production, leading to the loss of thousands of varieties of fruits, vegetables and grains unless the technology was properly regulated.

Critics of the Society’s position, including the British Soil Association, said the guide was neither neutral nor unbiased. "Everyone knows that there are at least some scientific controversies and disagreements about evidence concerning GM crops. None of these are mentioned in the Royal Society document,” the association said in a statement.

“The Royal Society's involvement in GM has been consistently one-sided, ignoring scientists with dissenting views, and overlooking facts which do not fit with the views of supporters of GM crops,” it added.

On the other side of the Atlantic, a new analysis by the advisory group the National Academies of Sciences, Engineering and Medicine has concluded that GM crops “appear to be safe to eat and do not harm the environment.”

However, the group said it is somewhat unclear whether the technology has actually increased crop yields. The 400-page report said also that new techniques such as gene editing are blurring the distinction between genetic engineering and conventional plant breeding, making the existing regulatory system untenable. It called for a new system that pays more attention to the attributes of the crop rather than how it was created.

This latest of several reports prepared by the National Academies – private, nonprofit organizations set up by the US Congress to provide advice on issues related to science, technology and medicine – was written by a committee of 20, mostly from academia, without any direct industry participation.

The committee examined more than 1,000 studies, heard testimony from 80 witnesses and analyzed 700 public comments. It focused its review on the GM crops that account for the vast bulk of those grown in the US, including corn and cotton containing bacterial genes that make the crops resistant to certain insects along with and soybeans, corn and cotton that are resistant to herbicides, particularly glyphosate, the main ingredient in Monsanto’s Roundup.

In conclusion, the authors said foods made from manipulated crops do not appear to pose health risks, based on chemical analyses of the foods and on animal feeding studies. However, one caveat was that “many animal studies are too small to provide firm conclusions.”

The report also looked at the incidence of certain diseases, in some cases comparing rates in North America, with Western Europe, where manipulated crops are less prevalent. It found no evidence that the GM crops had contributed to an increase in the incidence of cancer, obesity, diabetes, kidney disease, autism, celiac disease or food allergies. Its recommendation was that the regulatory system be tiered, with potentially riskier products receiving greater scrutiny, whether genetically manipulated or not.

While saying there is “no conclusive evidence of a cause-and-effect relationship” between manipulated and conventional crops as regards environmental problem, the US, like the British, scientists concluded that introduction of GM crops “does not appear to have accelerated the rate at which corn, soybean and cotton yields were already improving.”