Reproduction and cloning
Genetic engineering is also called genetic modification or GM. It is not the same as cloning. Although cloning techniques are used in genetic engineering, the two things should not be confused. The table shows some of the differences.
|produces exact copies||produces a unique set of genesgenes: The basic units of genetic material inherited from our parents. A gene is a section of DNA which controls part of a cell's chemistry - particularly protein production.|
|genes copied within the same species||genes can be swapped across species|
Certain enzymesenzymes: Proteins which catalyse or speed up chemical reactions inside our bodies can cut pieces of DNA [DNA: The material inside the nucleus of cells, carrying genetic information. DNA stands for Deoxyribonucleic Acid. ] from one organism, and join them into a gap in the DNA of another organism. This means that the new organism with the inserted genes has the genetic information for one or more new characteristics. For example, the organism might produce a useful substance, or be able to carry out a new function. We say that the organism has been genetically modified.
The animation shows how the method can be used to produce bacteria [bacteria: Single-celled microorganisms, some of which are pathogenic in humans, animals and plants. Singular is bacterium. ] that produce insulin. This is a human hormonehormone: chemical messengers produced in glands and carried by the blood to specific organs in the body and valuable to people with diabetesdiabetes: a serious disease in which the body is unable to regulate blood sugar. Bacteria reproduce quickly, so a lot of insulin can be made quickly.
You may wish to view this BBC News item from 2005 about some hostility in France towards GM crops.
There are strong arguments for and against cloning and genetic engineering. It is possible to produce genetically modified animals and plants. Sheep that produce human proteins for treating the symptoms of cystic fibrosis - a disease which causes sufferers to produce abnormally thick and sticky mucusmucus: Slimy white protein, which lines the respiratory tract and alimentary canal. in their lungs - have been produced, and even tobacco plants that glow in the dark when they need watering.
Some people are excited by the almost limitless possibilities of cloning and genetic engineering, while some people believe the process is unethical and should be banned. Others are concerned about what might happen in the future.