Genetic Engineering

It is now possible to manipulate an organisms genetic information by cutting a section out of one cell's DNA and splicing it to another cell's DNA.

This allows the genetically modified cell to behave differently - for example, it may excrete a chemical it wasn't able to make before.

Limitations:

Currently, we can only do this to one cell at a time, so it is only possible to genetically modify bacteria and other single-celled organisms. Genetically modifing a plant or an animal must be done when the plant is a seed or the animal an embryo.

There are also many ethical and moral dilemmas surrounding the possiblility of genetically modifying plants, animals, or humans. Some people are also concerned about the potential effect GM plants could have on the environment.

Uses:

We are already using this technology every day.

Bacteria have been genetically modified to produced human insulin. A single cell is taken from a human who is able to produce insulin, and the DNA regulating that production is cut out of that cell and spliced into the bacteria's DNA. It begins to produce insulin, which we then collect and use to help people with diabetes.

We have also begun to genetically modify plants such as wheat and rice, to make them grow faster or to make them produce toxins to ward off pests. These GMO crops are already widely grown and used in food production.