What is the technology of genetically modified food?

● Genetically Modified Crops (GM Crops)

Definition: any crop that is modified or recombined hierarchically at the genetic level using molecular biology and gene transfer techniques to achieve a specific goal, such as increased resistance to adversity, or the production of a special product, can be called genetically modified crops, or GM crops (Genetically Modified Crops).

Genetically Modified Technology (GMT): Technology related to the use of genetic engineering or molecular biotechnology to transfer (or transpose) genetic material into living cells or organisms, resulting in the phenomenon of genetic modification; but does not include traditional breeding, cell fusion, protoplasmic fusion, hybridization, mutagenesis, in vitro fertilization, somatic mutation and chromosome doubling, and other technologies.

●GM crop research and development

Traditional crop breeding utilizes seed selection, mutagenesis, and intraspecific or near-origin crosses, and basically the "source of variation" is limited to intraspecific genes.

GM crop research and development, on the other hand, directly targets genes, the source of which is "not restricted to species-specific genes".

The process of research and development mainly involves

1. finding genes

2. reconstructing genes

3. proximally delivering genes into plants

4. identifying the transgenic plants

5. field testing

6. testing and evaluating

●Genetic Transfer Methods

Plant There are many gene transfer methods, including particle bombardment, Agrobacterium, electroporation, PEG (polyethylene glycol), pollen tube, and so on. Currently, the particle gun method and the Agrobacterium method are almost always used.

(a) Particle gun method

The DNA is coated on gold particles with a diameter of about 1 - 1.6 μm, and then the gold particles are injected into the plant cells by helium propulsion. The particle gun method is non-selective for plant species and tissue cells, and is applicable to a wide range of applications, but it is necessary to find the most suitable culture system for each material, to understand the pathway of regeneration, and to select the most highly capable regeneration cells. However, for each material, it is necessary to find the most suitable culture system, understand the pathway of plant regeneration and select cells with high regeneration ability, or adjust the culture conditions to increase the number of cells with regeneration ability, and then target these cells for transplants.

(b) Agrobacterium method

Agrobacterium has Ti plasmid (tumor inducing plasmid), there is a section of T-DNA in the plasmid, which will pass through the injured plant cell wall, enter into the nucleus of the plant cell and merge into the plant genome, and tumors will appear in the infected plant, therefore, if you cut out the genes that lead to tumors in the Ti plasmid, and put the genes that are intended to be transgenic, it is an excellent method. Therefore, if the tumor-causing gene in the Ti plasmid is removed and the proposed gene is inserted, it is an excellent transgenic system.

●●●Impacts

●Positive impacts:

Improve the yield and nutrition of GM crops, and improve the resistance to pests and stress

Reduce the impact of pesticides on the environment

Soil and water conservation

Phytoremediation: GM plants or microorganisms can correct the pollution of the soil, sedimentation, and surface of the ground in place. GM plants or microorganisms can correct in situ contaminated soil, sedimentation, surface water and underground aquifers (geological structures formed by aquifers containing permeable soil with water), and GM plants can effectively remove toxic heavy metals from soil and water by absorbing them into plant tissues.

●Negative impacts:

Wolfenbarger and Phifer (2000) summarize the risks of GM crops as including

(1) the risk of invasiveness

(2) direct impacts on non-target organisms and native species

(3) direct impacts on non-target organisms and species

(4) the risk of invasion of the plant. >

(3) Indirectly affecting non-target species: some species depend on pests to survive and reproduce, e.g. planting herbicide-resistant crops may prevent insects that specialize in feeding on seeds from finding food.

(4) Viral recombination (viral recombination) of antiviral transgenic genes may produce new viral diseases.

(5) GMO is so variable that it is likely to produce unexpected results.

Lifei Liu Genetically Modified Crops (Varietal Improvement of Crops).

Zhao Rongtai Environmental Risks of Genetically Modified Organisms. Forestry Experimentation Institute, Council of Agriculture, Executive Yuan.

Pan, T. M.. Status and Prospects of Genetically Transformed Foods and Microorganisms. Institute of Microbiology and Biochemistry, National Taiwan University.

Introduction to Biotechnology, Second Edition Susan R. Barnum

If you want to find other information, you can go directly to the website of the Department of Health, Executive Yuan