September 19, 2019The distribution system for genome-edited foods has been solidified, and it is now a reality that foods consisting of genome-edited crops will be on our dinner tables. By the time today's middle and high school students reach adulthood, genome-edited crops will be commonplace.
But on the other hand, what is genome editing? What is the difference between genome editing and genetic modification? and "How is its safety investigated? are still not well understood, not only among middle and high school students, but also among adults.
In order to foster in middle and high school students the ability to have correct knowledge about new technologies and to make choices based on their own judgment, we will use "genome editing" as a subject to propose discussion points in the educational setting and introduce examples of actual teacher practice.

Genome Editing Technology Continues to Expand

Genome editing is rapidly spreading in the field of crop breeding. The most well-known method is the use of CRISPR/Cas9, which was introduced in 2012. The advantages of genome editing for breeding are twofold: First, it can be used for all species. First, it can be used to improve plants that could not be improved before due to slow growth, inability to use conventional techniques, etc. Second, it can be used to change the exact location of the target plant. The other is that it is possible to change the exact location of the target. Compared to conventional breeding, where many varieties are crossed to produce a crop that happens to have the desired characteristics, the time required for breeding can be dramatically shortened. The speed is said to be about 10 times faster. It is expected that new crops will be developed in the future.

Are genome-edited foods safe? How is it different from GMO technology?"

On the other hand, consumers may have questions about the safety of crops produced by genome editing. When considering food safety, it is fundamental to consider food safety in comparison to conventional foods. Conventional food products are those that are made from crops produced by conventional breeding techniques, such as mutation in nature, human-induced mutation (chemicals and radiation), and crossbreeding.
Genome-edited foods are organized and categorized into the three types below.

Three types of genome-edited foods

• Type 1A small portion of the original gene has been altered.
• Type 2DNA: DNA made by altering a part of the original gene and putting it into the creature, thereby altering its genes.
• Type 3: almost the entire exogenous gene in it.

Of these, Type 1 is not considered to fall under the category of recombinant DNA technology because it is a genetic mutation that can occur in nature or in conventional breeding, and its safety is considered to be at the same level as that of conventional foods. Therefore, the rule states that safety screening as a genetically modified food is not required. However, the developer is required to submit detailed information. Almost all crops currently under development are of this type. On the other hand, Type 2 (or part of Type 2) and Type 3 crops, which ultimately contain foreign genes or other changes that cannot occur in conventional breeding, fall under the category of recombinant DNA technology and require a safety review by the Food Safety Commission in the same way as genetically modified foods.

What would happen if we used genome editing technology on humans?"

Now that we have looked at food, students may ask, "What would happen if we used genome-editing technology on living organisms other than plants (mainly humans)?" If we disregard ethical considerations, this technology could be used to create a new type of food. If ethical considerations are ignored, this technology can theoretically be applied to all living organisms, including humans. It is important to note that the risks and ethical issues differ greatly depending on whether one is dealing with germ cells (eggs and sperm) or fertilized eggs, or with somatic cells. In the former case, in principle, it is impossible to obtain the consent of the person who is to undergo the modification, and the effects of the modification will continue to affect his or her descendants. For this reason, reproductive medicine that involves genetic modification of germ cells or embryos is prohibited under the guidelines of the Ministry of Health, Labor and Welfare.

Here are some practical examples of teachers who were among the first to incorporate genome editing into their classes.

Someone," a science magazine for junior and senior high school students, carries articles on researchers involved in genome editing. We hope you will make use of it in your classes!

Special Feature: "Gifts for the Table"

Eat and be healthy! Speed Development of a New Tomato Seed
(Dr. Hiroshi Ezura, Professor of Life and Environment, University of Tsukuba)

Ties to create something that everyone can choose from.
(Masato Kinoshita, Department of Marine Bioproduction, Division of Applied Biological Sciences, Graduate School of Agriculture, Kyoto University)

Beyond steady research, super rice withstands drought!
(School of Life Sciences, University of Nevada Las Vegas Anne Jinky Villacastin)

Genetic modification and genome editing are not something that is far away in the distant world, but something that affects our lives as well. How these technologies should be used and what kind of rules should be established are issues that society as a whole and each of us should consider. Therefore, we aimed to foster the students' ability to think and make decisions on their own by making them aware of social issues related to genome editing as something close to them.

Program Flow

In the third semester of the first year of high school, students decide whether to take a liberal arts course or a science course. After the decision is made, liberal arts students sometimes feel that they do not need to study science-related subjects, while science students sometimes feel that they do not need to study liberal arts subjects, and we felt this was an issue. Therefore, we aimed to make the students realize that knowledge of both humanities and sciences is necessary in the real world by covering the latest topic in the field of science, "genome editing," in the modern society class I am in charge of.

Program Flow

*Reprinted from "Education Support vol. 47