Genetic engineering raises serious ethical and safety questions that scientists, governments and the public have been debating for decades. There are no simple answers.
Safety concerns
- Could the engineered organism harm human health? GM food has been eaten by millions of people for over two decades with no clear evidence of harm, but long-term effects are uncertain.
- Could engineered genes spread to wild populations? Pollen from GM crops can fertilise wild relatives. Genes for herbicide resistance, for example, could spread to weeds, making them harder to kill.
- Could engineered organisms unbalance ecosystems? Bt crops kill the target pests but might also harm non-target species like butterflies that share habitat with crops.
- Could pests evolve resistance? Yes. Insects exposed to Bt crops will be under intense selection for any Bt-resistance allele. Resistance has already been observed in some places.
- Risk of escape: GM fish or insects released could establish wild populations that crowd out natives.
Ethical concerns
- Playing God: some people feel humans should not deliberately alter the genome of any organism, especially across species boundaries. This concern often has religious roots.
- Animal welfare: transgenic animals may suffer from health problems caused by their engineered genes; cloned animals often have shorter lifespans and weaker health.
- Patents and ownership of life: companies can patent the GM organisms they create, treating living things as private property. Critics argue life should not be owned by corporations.
- Inequality: GM seeds and patented livestock benefit large agribusinesses more than small farmers. Some farmers become dependent on annual seed purchases from a single supplier.
- Reduced choice: cross-contamination between GM and non-GM farms can mean farmers and consumers lose the choice to avoid GM products.
- Human gene editing: the same technology can in principle be used on human embryos. In 2018 a Chinese scientist produced the first gene-edited human babies, triggering global condemnation and tighter regulation. The line between curing disease and "designer babies" is murky.
Reasons for cautious optimism
Genetic engineering has also brought real benefits:
- Insulin for millions of diabetics
- Vaccines produced quickly and at low cost
- Vitamin-enriched crops that could prevent millions of cases of malnutrition
- Drought-tolerant crops for areas facing climate change
- Medical research tools that have led to important discoveries
- Conservation potential for endangered species
The regulation question
Different countries take very different approaches:
- The USA treats GM crops mostly like any other crop, with limited labelling.
- The European Union is more cautious: GM crops must be labelled, and many are banned from growing in EU countries.
- The UK is currently relaxing some rules to allow more gene-edited crops.
- Many countries in Africa and Asia have a patchwork of approaches.
Whether genetic engineering is mostly a force for good or for harm depends partly on how carefully it is regulated, who benefits from the new technology, and how transparently companies and governments handle the risks.