Risks and benefits of GMOsSpec 8.22
In short
Genetically modified organisms bring benefits and risks. They can increase crop yield, resist pests, improve nutrition and make medicines. Risks include transfer of genes to wild plants, effects on non-target organisms and biodiversity, possible health effects, cost and ownership of seeds, and ethical objections to modifying organisms.
| Benefits | Risks | |
|---|---|---|
| Agriculture | Higher yields; crops resistant to pests (such as Bt crops), herbicides, drought or disease; less pesticide used; crops with added nutrients, such as beta-carotene (which the body converts to vitamin A) in golden rice | Genes may spread to wild relatives or weeds through pollen; pests may evolve resistance; non-target insects may be harmed; reduced biodiversity if only a few GM varieties are grown |
| Medicine | Large amounts of pure human proteins such as insulin; vaccines and antibodies made in plants and animals | Unforeseen effects of inserted genes; welfare of transgenic animals |
| Health | Foods may be more nutritious or free of allergens | Possible allergic reactions to new proteins; long-term effects not fully known |
| Economic and ethical | Cheaper food and reliable supply; benefits for food security | Seeds are patented and costly for farmers; some people object on ethical or religious grounds to modifying organisms |
In an ‘evaluate’ or ‘discuss’ question, weigh the benefits against the risks, give specific examples and reach a justified judgement. The evidence often depends on the organism, the gene and the environment, so each GMO may be judged separately.
Do not write that GM food ‘is unsafe’ or ‘is safe’ without evidence. Say what could happen and how it can be tested or controlled, for example by trials and monitoring.
Quick check
What is the role of a restriction endonuclease?
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It cuts DNA at a specific recognition sequence, leaving sticky ends.
What does DNA ligase do?
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It joins sugar–phosphate backbones of DNA fragments by forming phosphodiester bonds.
Why is a marker gene included in a plasmid?
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To identify the host cells that have taken up the plasmid.
What does a bright spot on a microarray show?
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That the gene with the matching probe is active, because mRNA from it was present.
What is bioinformatics?
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The use of computers and statistics to store and analyse large sets of biological data.
Written and checked against the Edexcel International A Level Biology (YBI11) specification · Updated October 2026