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Gene Hunters

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Tim Tully uses the creb gene to improve the memory of fruit flies.

If asked to name the animal scientists most often turn to in their quest to unlock the secrets of human DNA, your answer might be the chimpanzee, or the gorilla. While it's true that these apes are our closest genetic cousins, it turns out the rest of the animal kingdom is not far behind. Which makes the easy to manage fruit fly an ideal candidate for genetic testing.

Scientist Tim Tully, who has been working with these flies for years, has recently made some remarkable discoveries involving long-term memory. First Tully conditions a group of flies to associate an unpleasant tingling sensation in their feet with a certain chemical odor. He then lowers the flies, elevator-style, into a tube with this odor on one end, and another odor on the other. As one might expect, the flies crowd away from the chemical odor associated with the unpleasant sensation.

Photo of fruit flies
  Fruit flies have been favored by genetic researches for 100 years.

A week later the flies will forget their experience unless Tully exposes them to a series of trials, spaced about fifteen minutes apart. After these training sessions, the flies are able form a long-term memory of the unpleasant correlation. However, Tully has found that by giving certain flies a gene that our two species share, known as creb, these flies are able to remember to avoid the smell one week later after just one test, giving them the equivalent of a photographic memory. The possibilities of Tully's discovery are endless, from helping students cram for the big test, to treating debilitating conditions like Alzheimer's disease.


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