This avoids introducing other genes with undesirable traits. Genetic engineering also helps speed up the process of creating new foods with desired traits. These concerns have thus far been unfounded. None of the GE foods used today have caused any of these problems. They assess the safety of GE foods to humans, animals, plants, and the environment.
Cotton, corn, and soybeans are the main GE crops grown in the United States. Most of these are used to make ingredients for other foods, such as:. The World Health Organization, the National Academy of Science, and several other major science organizations across the globe have reviewed research on GE foods and have found no evidence that they are harmful. There are no reports of illness, injury, or environmental harm due to GE foods. Genetically engineered foods are just as safe as conventional foods.
Mouse models are engineered for biomedical studies, bacteria are engineered to produce medications such as insulin, and crops are engineered for agriculture. All of these products of genetic engineering were created using the same basic steps: identifying a trait of interest, isolating that genetic trait, inserting that trait into the genome of a desired organism, and then growing the engineered organism Figure 1. These steps are explained in detail below, using examples from Monsanto as the details of their technologies are publicly available.
Step 1: Identify a trait of interest In order to identify a desirable new trait scientists most often look to nature. Successful discovery of a new genetic trait of interest is often a combination of critical thinking and luck. For example, if researchers are searching for a trait that would allow a crop to survive in a specific environment, they would look for organisms that naturally are able to survive in that specific environment.
Or if researchers are aiming to improve the nutritional content of a crop, they would screen a list of plants that they hypothesize produce a nutrient of interest.
An example of a trait currently in GMOs that was identified through this combination of luck and critical thinking is tolerance to the herbicide Roundup see this article. Although it is not on the market in the United States, Syngenta has designed Golden Rice with an increased amount of pro-vitamin A, which the human body may turn into the vitamin A see this article.
Researchers at Syngenta identified the gene sequence that produces pro-vitamin A and compiled a list of plants to screen with that sequence [9]. With a little luck, there was a plant in nature, maize, that contained a gene that would make Golden Rice produce pro-vitamin A at a level that could meet the nutritional needs of vitamin A deficient communities.
The genomes of plants with the trait are compared to genomes in the same species without the trait, with the goal of identifying genes present only in the former [8]. The genomes of different species with the same trait may also be compared in order to identify a gene, as was the case while developing Golden Rice [9]. In order to expedite this process, Monsanto has developed and patented a method known as seed chipping [8]. Through this method Monsanto shaves off parts of seeds for high-throughput genetic sequencing while leaving the rest of the seeds viable for planting.
This creates a genetic database for plants before they are even grown, where a barcode system is used to match plants to their genotypes. Researchers may then use this database to identify new traits of interest as well as to optimize the desirable traits in a crop by selecting for the best genotypes based on plant phenotypes. Step 3: Insert the desired genetic trait into a new genome Altering the genome of plant seeds is difficult due to their rigid structure.
In biotechnology research it is common to genetically engineer bacteria to produce a desired protein. This is done by using enzymes to cut and paste a DNA strand of interest into a plasmid, which is a small, circular molecule of DNA [10]. Bacteria are then shocked using heat or electricity so that the cells accept the engineered plasmid. By modifying A. First, the genotype of the organisms must be checked so that researchers are only propagating organisms in which the genome was modified correctly.
Biotech companies invest large sums into keeping these plants alive and reproducing once they have been successfully created. The companies use special climate-controlled growth chambers, and biologists often check on the plants by hand to make sure that they are growing as expected [8].
Which foods might contain GMOs? Most packaged foods contain ingredients derived from corn, soy, canola, and sugar beet — and the vast majority of those crops grown in North America are genetically modified. To see a list of high-risk crops, visit the What is GMO page. Animal products: The Non-GMO Project also considers livestock, apiculture, and aquaculture products at high risk because genetically engineered ingredients are common in animal feed.
This impacts animal products such as: eggs, milk, meat, honey, and seafood. Processed inputs, including those from synthetic biology: GMOs also sneak into food in the form of processed crop derivatives and inputs derived from other forms of genetic engineering, such as synthetic biology. Because GMOs are novel life forms, biotechnology companies have been able to obtain patents to control the use and distribution of their genetically engineered seeds.
Whereas humans have half a set of chromosomes structures that package and organise your genetic information from each parent, some organisms can have two or more complete duplicate sets of chromosomes. Without realising, many crops have been unintentionally bred to a higher level of ploidy entirely naturally as things like large fruit or vigorous growth are often desirable.
Ginger and apples are triploid for example, while potatoes and cabbage are tetraploid. Some strawberry varieties are even octoploid , meaning they have eight sets of chromosomes compared to just two in humans. Yet asexual reproduction is the core strategy for many plants in nature, and farmers have utilised it for centuries to perfect their crops. Once a plant with desirable characteristics is found — a particularly tasty and durable banana, for instance — cloning allows us to grow identical replicates.
This could be entirely natural with a cutting or runner, or artificially-induced with plant hormones. Selection — both human and natural — operates on genetic variation within a species. If a trait or characteristic never occurs, then it cannot be selected for.
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