In 1983, Barbara McClintock was awarded the Nobel Prize in Physiology or Medicine for her discovery of mobile genetic elements or “jumping genes.”

McClintock discovered mobile genetic elements in plants more than 30 years ago was made at a time when the genetic code and the structure of the DNA double helix were not yet known. It was only recently that the biological and medical significance of mobile genetic elements has become apparent. This type of element has now been found in microorganisms, insects, animals and man, and has been demonstrated to have important functions.  McClintock proved that genetic elements can sometimes change position on a chromosome and that this causes nearby genes to become active or inactive.