Gene Guns

Gene guns are devices that are used to project very small pieces of metal, such as gold or tungsten, into plant tissue. These pieces of metal are covered with the DNA material of interest before they are "shot" into the plant tissue. The first gene guns actually used a 22 mm pistol. When fired, the bullet hit a metal disc covered with the metal pieces covered with DNA. The metal particles penetrate the plant cells, placing the DNA into the plant cell cytoplasm and nucleus. The plant may then incorporate the DNA into its genome. Now gene guns use compressed gases instead of a bullet to do the same thing.

• What is the mechanical difference between a gene gun and pneumatic device to administer vaccines to people?
• What is the difference in effect in depth of tissue penetration between a gene gun and pneumatic device to administer vaccines to people?
• Why is it necessary to use metal pieces coated with DNA?
• Why do you think that gene guns are used more with plants than with animals?
• Can you think of any situation where you would use a gene gun with an animal?