What if you could take a drug that would quickly alter your sexual orientation from straight to gay, or vice versa?

To their surprise, neurobiologists have discovered that homosexuality can be turned on or off in fruit flies. They’d known that sexual orientation can be genetically programmed, but they didn’t realize it could also be altered by giving a drug that changes the way the flies’ sensory circuits react to pheromones.

Within hours of the treatment, previously heterosexual male fruit flies would be courting other males, and treatment could also cause flies who had been engaging in homosexual behavior to become exclusively heterosexual, the neurobiologists report in Nature Neuroscience. You can read a summary of it here from the University of Illinois at Chicago, the home of one of the researchers, David Featherstone.

“It was amazing,” Dr. Featherstone said. “I never thought we’d be able to do that sort of thing, because sexual orientation is supposed to be hard-wired. This fundamentally changes how we think about this behavior.”

I asked Dr. Featherstone if it might be possible one day to quickly alter humans’ sexual orientation. Here’s his answer:

Although I am not sure my research is a big step in this direction, I think that ultimately the answer will be: Yes. After all, the goal of neuroscience is a complete understanding of brain function. Understanding in science is typically demonstrated by the ability to control a process. This morning, I received an email from a transsexual 5 years into her hormone therapy. She told me she regularly modifies her libido and orientation with diet and drugs. She even sent me a scientific reference explaining why her regimen might work. Now that is amazing research. The question of whether or not homosexuality should be turned on and off is not a scientific question. It is an ethical/societal dilemma. I am glad my work is stimulating the discussion earlier rather than later. History is replete with poorly thought out attempts to ‘cure’ societal/behavioral ‘illnesses’ that turned out, with proper perspective, to not be ‘illnesses’ at all.

So let the discussion begin. I don’t think of homosexuality or heterosexuality as an “illness” to be “cured,” but I wonder how people would use the ability to control sexual orientation — to have a designer libido. Would some people, gay or straight, who weren’t having luck attracting one gender decide to switch to the other? Would some people casually switch back and forth?

Would some social conservatives (like Leon Kass), who normally object to biologists “playing god” and pharmacologists altering “human nature,” change their minds and urge the use of biotechnology to promote heterosexuality? Would some social liberals try to restrict the use of this biotechnology? Would parents, gay or straight, want to regulate their children’s sexual orientation — and should they or their children be allowed to do so?