Gay Gene in Fruit Flies?
According to gay.com, yes!!! Their headline is “Study finds gay gene in fruit flies” but unfortunately that’s not what the study actually found. gay.com says:
Researchers in Chicago have discovered a gene that identifies homosexuality in fruit flies, which can be turned on and off with drugs. David Featherstone, a biologist at the University of Illinois, said that while humans have a similar gene, it has yet to be determined whether that gene has any effect on same-sex attractions in humans.
Hmmmm… The Chicago Sun-Times has a much better telling of what the researchers actually found:
Researchers have discovered a gene involved in homosexual behavior in the tiny flies. They also found a way to turn homosexuality on and off with drugs.
Humans have a similar gene. But it’s unclear what effect, if any, the gene has on homosexual behavior in people, said biologist David Featherstone of the University of Illinois at Chicago.Featherstone and colleagues described their findings in the journal Nature Neuroscience.
After a century of study on fruit flies, researchers have accumulated a vast storehouse of genetic knowledge. UIC researchers were using fruit flies to study muscular dystrophy when they discovered a gene they call “gender blind,” or GB.
Flies with a mutated form of the GB gene are bisexual. It appears they’re unable to distinguish chemical smells, called pheromones, that tell whether other flies are male or female.
“The GB mutant males treated other males exactly the same way normal male flies would treat a female,” Featherstone said. “They even attempted copulation.”
The GB mutation appears to strengthen nerve cell junctions called synapses. This causes flies to over-react to pheromones. As a result, they “broaden their horizons and go for both males and females,” Featherstone said.
Researchers tested this idea by adding a drug to the flies’ apple juice. The drug weakened the synapses. So within a few hours, flies with the GB mutation stopped engaging in homosexual behavior.
Conversely, researchers gave heterosexual male flies a drug that strengthened their synapses. Sure enough, these male flies soon were courting males as well as females.
“It was amazing,” 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.”
Did that make sense? Let me break it down for you:
- There is a gene in fruit flies that when mutated affects the synapses in the brain of a fly. This causes the fly to not be able to distinguish between male and female pheromones. This means that the fly is unable to distinguish between the sexes and attempts to mate with either.
- Adding a drug into the fly’s system weakens the strengthened synapses and enables them to distinguish between the sexes
- Conversely, adding a drug that strengthens the fly’s synapses causes the same effect as the faulty gene
This is not therefore a “gay gene” as gay.com (and others) are trumpeting. Rather it’s a gene that affects the brain and causes a malfunction of the pheromone detective abilities of the fly. More importantly, it’s easily rectified by simple drugs.
Human synapses are constantly changing as our brain adapts to environmental stimuli. For example, the taste and touch synapses evolve not just during gestation and childhood but over a whole lifetime as the brain learns response to physical actions. Essentially, synapses “learn” and adapt to our behaviour. For example, if you regularly drink strong spirits (vodka, schnapps etc) your reaction to them changes. The first time ever you down a shot it will burn your mouth and throat out. Your hundredth shot doesn’t have nearly the same effect and this is because the synapses in your brain that handle taste have adapted their response after multiple experiences of the alcohol. However, stop drinking for a few years and then have a shot and you’ll notice that it affects you again. Your synapses that handle taste have changed to adapt to your “non alcoholic consumption” lifestyle.
Or to take another example, when I was growing up I hated courgettes, Loathed them to the nth degree. But then in my late teens I started deliberately choosing to eat them and guess what? After a year or so I discovered that instead of hating the taste of courgettes I actually loved them. The synapses in my brain had altered in response to my changed behaviour, so what was previously a turn-off actually became a turn-on.
(Of course nothing is ever, ever going to get me to eat brussel sprouts. That’s one thing where I’m not even vaguely attempting to alter my synapses. But I digress.)
Or to take yet another example, the “brain training” games that you can buy for your hand-held video consoles or do online are nothing more than synapse altering techniques. Repeat a certain exercise enough times and your brain gets better at it. Why? Because the synapses alter in response to your repeated experience. You use “brain training” to literally rewire your mind.
That all makes the last paragraph in the Sun-Times report really interesting. Here it is again:
“It was amazing,” 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.“
What he’s saying very simply is this – the study showed that the sexual orientation of fruit flies was not hard-wired by the gene. Rather, it was flexible and alterable, dependent ultimately not on the gene but upon the condition of the synapses. So the gene was not after all a “gay gene” because it simply affected but did not ultimately dictate a separate behavioural response. Change or train the synapses (something we all do every day of our lives) and the behavioural response altered.
But of course, those of us who have seen a change in our sexuality knew that all along.