Greenpeace removing genetically engineered maize from trial farm in the UK.
How does genetic engineering work?
What is a gene?
Every plant and animal is made of cells. Every cell contains a
nucleus. Inside each nucleus are chromosomes, which act as
containers for strands of DNA (deoxyribonucleic acid). DNA is often
described as a blueprint containing all the necessary information
for the structure and functioning of an organism. Genes, which are
contained within strands of DNA, are the individual messages that
make up the blueprint - the basic instructions for life - and each
gene codes for a particular trait. Sounds simple, right? But
organisms aren't machines. And no gene functions in isolation. Life
is a delicate tangle of genes and organisms and environment. While
advances in genetics hold incredible potential in the medical
field, the genetic manipulation of food is still highly
experimental, and fails to take into account the incredibly complex
relationship of genes to organisms and organisms to the
environment.
What is the difference between genetic engineering and
traditional plant breeding?
Natural breeding techniques create new varieties by selecting
traits from the multitude that already exist within an existing
species. In nature, genetic diversity contains certain limits. A
rose can be crossed with another variety of rose, but it can never
be crossed with a mouse. Unlike natural breeding, genetic
engineering consists of taking genes from one species and inserting
them into another in the hopes of transferring a particular trait.
For example, scientists have attempted introduce a gene for
resisting the cold from an Arctic fish into tomatoes to prevent
freezing. It is impossible to predict, in the long term, how
transplanted genes will react within generations of organisms and
in the environment.
Want to know more?
Explore an illustrated guide to the problems of genetic
engineering, the complexity of gene expression and the unexpected
effects so far.
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Genetic Engineering: Living on a Flat Earth, PDF, 472K)