Green activists have long gained fame and fortune by campaigning against genetically modified foods, which they denounce as “monster foods” that can ruin traditional agriculture and decimate the human race. They claim scientists that splice genes from one organism into another are committing crimes against nature and creating Frankenstein monsters.
This is a mix of superstition and pseudo-science parading as real science. The campaign against GM crops has succeeded in scaring many politicians and judges into acting against genetically modified crops. Genetic splicing has produced some of the most high-yielding crops in the world (including Bt cotton in India). Indian farm leaders like Chengal Reddy constantly emphasize that GM corn, soybean and wheat are grown perfectly safely in dozens of countries, boosting farm income even while raising consumer supplies.
The US does not curb GM crops, so Americans have eaten a trillion meals of GM crops — without a single demonstrable health risk. Ironically, Europeans who fear GM foods happily visit the US as tourists and eat GM foods there, with no adverse results. If even a trillion cases cannot convince the activists, nothing will. Theirs is a triumph of ideological faith over common sense.
Scientists have for many years established the existence of gene flow, or horizontal gene transfer, between species. So, genetic transfers are not a human invention at all — nature has been doing it for millennia. This is one reason that led Mark Lynas, one-time campaigner against GM crops, to make a U-turn and denounce the activists instead.
As long as genetic transfer was thought to be a man-made invention, activists could call it unnatural and dangerous. But if humans have simply started doing what nature has done for millennia, how dangerous or unnatural can it be?
Initially, some scientists thought that natural gene transfers took place mainly in simple organisms like bacteria. Only recently has it become clear that gene transfers are extremely widespread in nature across many species. Even human beings have received gene transfers over the millennia, and so today carry genes that originally came from alien sources like fungus, bacteria and algae. Does this genetic intrusion mean humans are monster species? Hardly.
The Economist magazine recently carried an article titled “Genetically modified people”, drawing on research by two Cambridge scientists, Alastair Crisp and Chiara Boschetti, who have so far identified as many as 145 genes that have crossed over from other species to humans. Research on these issues has barely begun, and could in due course reveal thousands more gene transfers into humans — after all, nature has had lots of time to make such changes.
The Cambridge scientists found that one gene, which helps hold cells together, crossed over into humans from a fungus. Another gene, associated with fat mass, appears to have originated in marine algae. A third gene that helps define blood groups appears to have originated in bacteria
The scientists also looked at gene transfers in nine other primate species, 12 fruit fly species and four nematode worms. Fruit flies and worms multiply fast and so have long been used for biological research by scientists, helping create a vast body of scientific data.
The Cambridge scientists had to consider the possibility that what looked like gene transfers between species might actually be just genes from a common ancestor of the two species many millions of years ago. Now, genes from another animal could very possibly be the result of an ancient inheritance. But genes in animals that came from plants or bacteria would almost certainly represent horizontal gene transfer. The scientists found that, on average, worms had 173 gene transfers, fruit flies had 40, and primates had 109. Humans, with 145 transfers, turned out to be more genetically modified than other primates.
The researchers found two imported genes for amino acid metabolism, 13 for fat metabolism and 15 for modifying large molecules. They identified five immigrant genes that generated valuable anti-oxidants, and seven that aided the immune system.
This is a story of genetic success, not risk. But if so many gene transfers into humans or crops were attempted by scientists, activists would be enraged. Politicians and judges who ultimately decide on crop rules must be made fully aware of how widespread gene transfers are in nature, and how not even a trillion GM meals have disclosed any dangers.
Activists have responded by saying that natural gene transfers took place over centuries, giving every species time to adapt. True, but whenever a natural gene transfer occurred, it was just as alien as the insertion of a Bt gene into brinjal or cotton.
All crops, including GM crops, are routinely field-tested for safety before commercial release. But to stop even field trials (as activists want) is a pseudo-scientific form of religious frenzy.