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Genetic Modification, from Benefits for Peasants to Taste and Nutrition

Editor’s Note: This is the 30th anniversary since human’s realization of genetic modification (GM) technology. Nature magazine prepared a battery of GM topics introducing the history of this biological technology slogging in all kinds of debates and wrestling, the development situations in various countries world widely, the novel and in-progress technologies, as well as the future for GM technology. This article is the second of the series, which in a technical point of view narrates the development of GM technology. In the past 30 years, the continuous advancement of GM technology not only benefits peasants and agricultural corporations, but also benefits final consumers in terms of taste, nutrition and reassuring the public.

*This article was originally published on Scientific American by Daniel Cressey.


As the advancement of GM technology, the number of benefited people keep growing—peasants increase their income while consumers have better tastes.

*Image source: shutterstock.com

As Anastasia Bodnar said, when they were developing on the first batch of genetically modified crops, “We seem to see rocket jetpacks.”—The future super-nutrient crops could bring exotic products and feed the hungry world. Bodnar is a biotechnology expert who works non-profitably to advocate Biology Fortified GM technology.

Up till now, however, Bodnar said that the majority of the benefits of GM technology comes to agricultural corporations—the profit point is almost the crops that are genetically modified to be resistant to insecticides and pests. By growing these crops, peasants can obtain higher production and reduce the amount of insecticides needed.

The problems is, traditional consumers are not sensitive to such advancement, said Bodnar. On the contrary, the advancement pours oil on the flames of objecting GM technology. The objector believe that GM technology helps concentrate power and interest within a few major companies. Additionally, genetically modified crops are the best evidences for “scientists ignoring dangers and interfering the nature”.

However, today is the time that the new generation of genetically modified crops are going to enter the market from the laboratory, and the situation might change. Ranging from apples that slow down their color-changing process, orange-colored bananas, to nutrition enhanced golden rice that can improve diet of impoverished nations, the new crops are ready to solve new problems.

Some advanced GM technologies will be applied into the new generation crops, which are able to edit the genomes of plants more precisely. Using this approach, there is less demand to transfer genomes from other breeds into cash crops and this is also a major attack point of objectors for GM technology. With this feasible approach, the anxiety of the public on genetically modified food should be alleviated.

However, this might not always the case. No matter how bright the future these crops demonstrate in the lab, they must prove their value through labor and cost consuming field trials and eliminate the common public doubts. The last step is pretty difficult, Philip Bereano said. Bereano was studying on the influence of new technology on the public and he pointed out that genetically modified creature related debates covers aspects of safety, labeling, and ethical issues of patent application. “People all care about what they feed their children,” he said, “and this is not going to change.”

Even so, most researchers in GM field are confident to believe that the most difficult technical issue has been overcome and the future is bright. If we are looking eagerly for a skyrocketing time of genetically modified food, Bodnar said, “This is the time.”

The first wave of genetically modified crops are oriented to peasants and the aim is to relief their working burden and help them achieve higher production with more interests. For example, in 1966, a biotechnology company, Monsanto, brought out their first best-selling breed, “Roundup Ready”. It was a soybean breed, which was incorporated with bacteria genes so that it can withstand the herbicide “Roundup”, which also came from Monsanto. This means that peasants could use only one kind of herbicide and handle most weeds, in the same time protect the crops. Right after that, more and more genetically modified crops were brought to the world, including the Bt cotton from Monsanto, which was modified to generate a toxin that can kill bollworms and thus, the demand for insecticides was reduced.

Peasants will still be the main target of new generation genetically modified crops. For an instance, scientists from Rothamsted Research Center, Harpenden, UK, are developing a new crop that requires less or even no insecticides compared with Bt cotton. The thing that play vital role in these crops is a warning ectohormone that are generated during the evolution of some wild plant breeds and this ectohormone can mimic the chemical warning signal released by aphid (a major pest in temperate zone )in danger. When this chemical defensive substance is transferred into wheat, the pests will believe that they are in dangerous situation and hence they will be expelled. What differs this crop with Bt wool and all present genetically modified creatures is, it totally needs zero insecticides for pest protection.

Principal in Rothamsted Research, Maurice Moloney said that they were in the process of field trials. “It works great in the greenhouse,” he said, “If it is feasible to apply it into the fields, we are going to take full advantage of that and make it a stable character so that it can be suitable for mass growth.”Moloney said, they hope to widen the research with the results and seek for other protective and warning factor from natural evolution, and study on how to enhance or control the factors to confront certain pests. “For example, we can use a volatile compound to deter caterpillars and longicorn beetles,” said Moloney, “if we are able to produce things like this, the range for application will be surprisingly wide.”

From Cassava to Apple

A lot of scientists who are working on genetically modified crops are devoted to issues that are not being focused by major companies. For example, in ETH Zurich, Herve Vanderschurenand his botanic biotechnology group is researching on cassava, a tropical shrub and the tuber of which is the principal food for some developing countries. He said: “No one wants to make big investment for the crop’s growing and modification.”

Vanderschurenand’s group is working on using genetic engineering to insert genes that are resistant to cassava brown streak virus into natural mutants that are resistant to cassava common mosaic virus. Therefore, cassava that is resistant to both diseases is obtained. Vanderschurenand said, this genetically modified crop that is suitable for local environment is “an extremely important component of our current research”, which is a thing that global commercial companies are rarely willing to do. Vanderschurenand and co-workers have successfully cultivated the genetically modified crop and are now co-operating with universities in Africa to arrange field trials to make sure they could grow in fields.

The crop research in developing countries are mostly related with nutrition improvement and a famous example among them is golden rice.


In the above photo, left is the golden rice, the golden color of which comes from its unique β-carotene.*

*Image source: forbes.com

Rice is the principal food for more than half of the world’s population while the golden rice is a genetically modified breed. Its unique golden color comes from the added β-carotene, the precursor for Vitamin A, which is widely demanded to remedy Vitamin A lacking in diet for many East Asia countries. Since the first generation of golden rice came into stage in 2000, golden rice has been through years and years of endeavor and numerous questioning from anti-GM organizations, eventually it starts the field trails in Philippine. It is for sure that no later than 2014, golden rice can pass the final regulatory approval to peasants ‘hands.

Other crops are following closely. James Dale, the Director of Center for Tropical Crops and Biocommodities in Queensland University of Technology, Australia, is now working on bananas that are resistant to yellowtop and containing more β-carotene, iron and other nutritious elements. He explained that in African countries such as Uganda, “Microelement lacks very much”, and bananas are their principal food. Currently they are conducting field trials in Australia.

Although most of the new generation genetically modified crops aim at peasants, there are several of them target on the next step in the food production chain: food processors. For example, plant molecular biologist Chris Dardick from Appalachian Fruit Research Laboratory, U.S. Agricultural Research Service, explained that traditional plum are difficult to process since when dealing with plums, there will be sharp and hard fragments left. Currently, they are performing a research that modifies a conventionally breeding plum which has almost no kernel to obtain fruit with no kernel at all. “What we care most is whether this stuff can be accepted by the industry and consumers. Based on the feedback we have, it seems good. “He said.

The following task is to design genetically modified foods targeting final consumers. One of the pioneers is “Arctic Apple”, which features in slow color changing when compared with traditional apples.  It is a benefit from GM technology and the inserted genes come from some breeds with low level of polyphenol oxidase (an enzyme that leads apple to change to brown when it has been cut or bite).

Arctic Apple

In the above photo, the right one shows the “Arctic Apple” that features in slow color changing process.*

*Image source: ucce.ucdavis.edu

“My wife and I are both apple farmers, and we are worrying about the decreasing consumption of apples. “Said Neal Carter, President of Okanagan Specialty Fruits, which is the developer of Arctic Apples.  Carter said, apples in supermarkets are gradually substituted by washed and sliced, open-to-eat fruits. If apples can be processed to similar food that does not change color easily, then it becomes a big fortune for food industry. If the result for apple is good, Carter says, we will try arctic avocado, pear or even lettuce.

The next move of GM.

By far, GM research rely on technologies that are mature but extensive, for example, “gene gun” is an approach that coats gold nano particle with DNA from other breeds and then shoots into target plant’s cells and hence the DNAs are randomly inserted. New tools can increase the accuracy of modification. For an instance, transcription activator–like effector nucleases (TALEN) and zinc-fingernucleases (ZFN) can be cut at particular positions according to people’s needs. By controlling the repairing of DNA gaps, it is possible to introduce a single nucleotide or a whole segment of genes at precise location, said Dan Voytas from Minnesota University, United States. “Because we know the exact location of gene insertion, we understand where the foreign gene is on what position of the chromosome. “ Thus, researchers can choose the best location to allow new gene expression and decrease the interference from the genome of the plant itself. Voytas’s group has successfully transferred anti-herbicide genes into tobacco plants using ZFN; while, some other groups utilize ZFN to insert anti-herbicide genes into corns or use TALEN to cut Xanthomonas oryzae genes from rice plants.

However, as Voytas explained, the real power of these technologies is to gain new characters by modifying the original genes of plants. For example, if researchers want to obtain drought-resistant plants, they can adjust multiple genes from the plant to achieve the goal without transferring drought-resistant genes. “In fact, the next move of GM technology is to introduce and adjust multiple genes simultaneously. “ He said. Derek Jantz is one of the co-founders of Pescision BioSciences, an American biotechnology company, and he is very interested in modification of plant genes. When Monsanto was breeding “Roundup Ready” crops, they transferred EPSPS gene from bacteria, however, almost every plant has similar gene, which means, by just modifying the genes in the plant without introducing foreign genes should also achieve the herbicide effect. Just like other researchers in GM companies, Jantz prefers not to talk about the specific programs in details due to trade secret. In a nutshell, he said, “What we want to do now is to take full advantage of the readily available functional genomics data.”

Genetic Breeding

Some researchers attempt to accelerate the development of traditional breeding technology via genetic modification approaches. Ralp Scorza and his group members from Appalachian Fruit Research Laboratory are now cultivating genetically modified plum tree. The genetically modified plum tree can only grow in greenhouse and if aspen genes are introduced, they will have an earlier and longer flowering time compared with traditional plum trees. That is to say, researchers are able to breed for the whole year and it only needs several years to breed disease resistances by screening and hybridization while in the past, it generally needs ten year or even longer. As soon as the desired characters have been developed, the genes that were introduced for flowering before could be knocked out so that new breeds are not genetically modified any more. Implementing such “fast” breeding strategy, Scorza and co-workers are devoted in breeding plum trees that are resistant to plum pox virus and also trying to increase the sugar content in the fruits. Similar strategies are also applied into citrus fruits by other researchers.

U.S. regulatory staffs suggest that these new plants should be treated differently from traditional genetically modified plants because they don’t contain DNAs from other breeds. This might alleviate the anxiety of the public. Molecular Geneticist Alan Mchughen from University of California, Riverside, said, “We are confident to alter the opinions of half of the objectors.”

In addition, Bodnar also mentioned that it is difficult to ban genetic modification experiments. She pointed out that genetic engineering has a relatively low threshold that “biohackers” can perform genetic modification experiments in their home or garage. In the future, some technologies are also easy to be applied on plants and animals.

“It’s becoming much easier.  People are eager for this stuff, “said Bodnar. “Rocket jetpack is something that everyone wants and now it is the time. The market doesn’t provide the environment by the up and down, but the grass roots will flourish themselves.”