Genetic modified foods (GM foods), which were known as the foods produced from organisms that have had specific changes introduced into their DNA using the methods of genetic engineering.
Since Anton Van Leeuwenhoek invented the microscope, it had been used for food production for a long time. It was considered as the first method to help modifying food.
In 1871, Louis Pasteur discovered that heating juices to a certain temperature could kill dangerous bacteria. Enzymes were discovered later in the 20th century. Their role in fermentation and digestion was also confirmed and put in use of producing foods. One example of applying this technology into producing food was using genetically modified microbes, which can secrete larger amount of enzymes, to accelerate the process of clotting milk and coagulate cheese curd.
In 1946, scientists discovered that DNA transfers between organisms. Later, in 1983, scientists succeeded in genetically modifying tobacco with the help of antibiotic resistant technology. Genetically modified food was soon approved to sell in markets. In 2015, 92% of corn, 94% of soybeans, and 94% of cotton produced in the US were genetically modified.
In US, corns are genetically modified to tolerate various herbicides and express a protein from Bacillus Thuringiensis that kills certain insects. Among all the corn acreages in 2010, 81% of corn acreages contain the bacillus thuringiensis genetic modification, and 89% of corn acreages contain a glyphosate-tolerating genetic modification.
Other than corn, the soybean is another crop that was widely genetically modified food. The genetic modification of the soybean enables it to tolerate herbicides, express bacillus thuringienisis, and also produce healthier oil. In 2015, 94% of soybean acreages in US are genetically modified to tolerate glyphosate.
Genetic modifying technology was also used in producing fruits other than crops. Today, 80% of Hawaiian papayas are genetically modified. In China, 95% of papayas in Guangdong province are genetically modified, and this is the same in Hainan province. In US and Canada, 13% of zucchinis are genetically modified.
Although genetically modified food has developed with an astonishing speed, there are still some concerns about genetically modified food.
The first concern is the crossbreeding issues with the wild population. Plants rely on transferring pollen to reproduce, and it is hard to control the transfer of genetically modified pollen via air. Although the effect of mixing the genetically modified organisms’ genes and native organisms’ genes remains unknown, critics cite that there is a need to learn the long-term effect of crossbreeding with native organisms before massive production. Obviously, this is highly concerned by the US federal government, and three US agencies are regulating the crossbreeding this issue.
Genetic variety is another concern of genetically modified food. Once the farmer started to grow genetically modified crops, they might stop growing the old varieties. These old varieties are important sources of diverse genes that give plants other desirable characteristics. For example, if a farmer grows only genetically modified corn, the genes are always the same. If there is a genetic defect, a certain disease or insect can cause an enormous damage and destroy the corn acreages. However, the old varieties may contain genes that help the crop defending them, and the crossbreeding process will enable new varieties to resist the diseases as well.
The third concern is about the toxicity and allergic reactions. Unlike countries like Australia and China, which has certain laws that requires the companies to label the genetically modified food, the USA has no contemporary laws. Labeling of genetically modified crops would allow people who have allergic reactions and opponents of genetically modified food to avoid them. It is hard to tell if the genetically modified food has allergic ingredients or not, so there is a high risk of people becoming allergic.
Citations:
Genetic modified food, Wikipedia
Genetic Modified Food, genetic learning center, University of Utah