The Buzz on Nature and Nurture

Inside a lab in Gardner Hall, they are getting drunk, beating up on one another, and getting poked in the eyes. It’s not an instance of out-of-control students, only scores of fruit flies taking part in an international genetics research effort. NC State’s Drs. Trudy Mackay and Robert Anholt are teaming with the Baylor University College of Medicine and scientists in a half-dozen foreign countries in a systems approach to determine how physical and behavioral traits are effected by genes and the environment.

Mackay is the William Neal Reynolds Distinguished Professor and Distinguished University Professor of Genetics. She is also the 2007 winner of the O. Max Gardner Award, the UNC Board of Governors’ highest faculty honor. Anholt is a professor of zoology and genetics, and the director of the W. M. Keck Center for Behavioral Biology.

Mackay spent a year inbreeding 40 strains of Drosophila melanogaster captured at the State Farmers Market in Raleigh. Twenty generations later, the insects in each line are genetically identical, allowing scientists to note any variation in traits caused by environmental differences. Once the genome of each strain is sequenced at Baylor, researchers will be able to look at how genetic differences are expressed. “We’re interested in the traits in and of themselves,” Mackay says. “We want to see how genes work together. We don’t know how many genes affect each complex trait.”

“This could open up a new view for looking at population variation and help achieve the goal of individualized medicine.”

Because the same genes are recognizable across species, scientists hope to correlate their findings to humans. “We can accumulate large amounts of data quickly using flies,” Anholt says, “and it’s statistically valid since we are able to control their environment and genetic background.” Already, the husband and wife researchers in the College of Agriculture and Life Sciences have measured how quickly different fruit fly strains become intoxicated on ethanol vapors to zero in on a few genes that seem to form a metabolic pathway related to alcohol sensitivity. They are translating their results from flies to humans by using longitudinal data collected on 1,700 participants in the 60-year-old Framingham Heart Study.

Similarly, Mackay and Anholt are studying the genetic basis of aggressive behavior in the flies by observing how they fight over food. They also have developed a fly model for ocular hypertension—a common risk factor for glaucoma—and are checking the insects’ olfactory function. Using the same fruit fly lines, their international partners are studying traits like development and learning and memory. As the studies progress, the researchers will move beyond genes into protein and metabolic impacts on traits. “This could open up a new view for looking at population variation,” Mackay says, “and help achieve the goal of individualized medicine.”

 

Forty strains of Drosophila melanogaster have been inbred to produce genetically identical insects for research. (Photo courtesy of Richard Lyman)

Forty strains of Drosophila melanogaster have been inbred to produce genetically identical insects for research. (Photo courtesy of Richard Lyman)

Drs. Trudy Mackay and Robert Anholt hope to use findings from studies on fruit flies to determine the genetic basis for human physical and behavioral traits.

Drs. Trudy Mackay and Robert Anholt hope to use findings from studies on fruit flies to determine the genetic basis for human physical and behavioral traits.