21.4 - Genetically Modified Organisms
- 1Creating genetically modified crops
- 2Creating genetically modified animals
- 3Creating genetically modified microorganisms
- 4Ethical issues surrounding patents in genetic engineering
Creating genetically modified crops
Genetic engineering is a tool that can enhance crop plants by making them resistant to herbicides or insects. Competition with weeds and insect pests can significantly reduce yields, impacting global food security so genetically modified (GM) crops can be very useful.
For example, soybeans can be genetically engineered to be resistant to insects:
- Soybeans are a vital food source worldwide, and insect pests feeding on these plants can drastically lower yields.
- Through genetic engineering, soybeans have been modified to include a gene from the bacterium Bacillus thuringiensis (Bt).
- The Bt gene produces a protein that is toxic to many insect pests but is harmless to humans and other organisms.
| Advantages of GM crops | Disadvantages of GM crops |
|---|---|
| Involves less labour than traditional herbicides and pesticides. | Encourage monocultures, reducing biodiversity. |
| Cheaper than traditional herbicides and pesticides. | Herbicide-resistant GM plants may crossbreed with wild plants, creating herbicide-resistant weeds. |
| Herbicide-resistant GM crops allow the use of herbicides to kill weeds without harming the crop, increasing crop yield. | Loss of traditional crop varieties reduces genetic diversity, which makes crops vulnerable to disease and climate changes. |
| Insect-resistant GM crops are less likely to be killed by pests, increasing crop yield. | Non-target insects could be harmed by the toxin coded for by insect-resistant GM crops. |
| Insect-resistant GM crops reduce the need for pesticides, benefiting the environment. | Insect pests may evolve resistance to the toxin coded for by insect-resistant GM crops. |
Creating genetically modified animals
GM animals offer significant benefits across various industries, including agriculture and pharmaceuticals.
Advantages of GM farmed animals:
- Improves quality e.g. by enhancing disease resistance.
- Improves quantity e.g. by enabling year-round reproduction.
- Improves productivity e.g. through faster growth.
Pharming
Pharming involves the production of pharmaceuticals and human medicines by inserting human genes into other animals. This process allows for the extraction of pharmaceutical proteins from GM animals' milk or blood at high yields.
For example, goats can be genetically engineered to produce antithrombin:
- Antithrombin deficiency puts individuals at risk of excessive blood clotting, requiring regular antithrombin treatment.
- GM goats can produce the antithrombin protein in their mammary glands, offering a new source of this crucial treatment.
| Advantages of pharming | Disadvantages of pharming |
|---|---|
| Enables mass production of rare treatments. | Raises animal welfare concerns. |
| Makes drugs more accessible. | Can lead to animals being viewed solely as commodities. |
Creating genetically engineered microorganisms
GM microorganisms have many applications, including the development of new treatments for diseases. By genetically altering pathogens, researchers can turn traditional disease-causing organisms into tools for medicine.
For example, poliovirus can be engineered to target cancer:
- Cancer cells often possess receptors for the poliovirus.
- Disabling specific genes within the poliovirus can make a version that targets and kills cancer cells without causing polio.
- This innovative approach holds promise for developing new cancer treatments.
| Advantages of GM pathogens | Disadvantages of GM pathogens |
|---|---|
| Offers potential treatments for diseases previously deemed incurable. | Carries a risk of accidental infections and disease outbreaks. |
| Can produce essential medicines, antibiotics, and enzymes, such as insulin. | There's a danger that engineered pathogens could revert to their original, harmful form. |
| Useful in creating vaccines. | Could be misused in biological warfare. |
| Facilitates the creation of DNA libraries for research. |
To minimise these risks, researchers adhere to strict safety protocols.
Ethical issues surrounding patents in genetic engineering
The patenting of GM organisms (GMOs) allows innovators to control the use of their creations. This allows them to share discoveries and provides financial incentives for further innovation.
However, patenting GMOs introduces ethical concerns:
- The legal patenting of engineered organisms raises questions about global access.
- This especially affects smallholder farmers in developing countries who may be unable to afford patented seeds due to high costs and legal barriers.
There is a need for a balance between rewarding innovation and ensuring ethical access for those in need, highlighting the importance of equitable patent policies.