Gay Gene in Fruit Flies?

According to, yes!!! Their headline is “Study finds gay gene in fruit flies” but unfortunately that’s not what the study actually found. 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 (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.

12 Comments on “Gay Gene in Fruit Flies?

  1. Peter,

    If in fact, it was discovered at some future point that we could develop a drug in which ‘homosexuals’ could be changed in the same way as the flies, would you support it?

    Yours, Winston.

    • Now there’s a good question….

      I don’t think human sexuality is quite as simple as fly sexuality!! Most animals operate on an instinctive basis and sexual attraction is for sexual activity and nothing more. Human sexuality however is more complicated and is more than just sexual activity. It’s to do with intimacy and companionship and as such I don’t think we’re ever going to find a faulty synapse or a drug that sorts out the whole thing.

      • Hypothetically though, if we did manufacture such a drug, would you be proactive in ensuring that it was given to as many gay people as possible? I ask, as I am interested in imagining what a world would look like in which the same sex intimacy and companionship that gay people experience in their lives was no more. Would it be a better world? What would be lost?

        Yours, Mark.

        • Hmmmm…. – I’m not sure I would be “ensuring” that people took it. Rather I would encourage people to take it. I know that for myself and many others that heterosexual relating is much more satisfying than homosexual relating on both an emotional and spiritual level.

          But I think there would have to be a major public conscience shift before we got to that point. The whole point of advocating such a psychiatric drug is that the thing it is trying to correct is in error. At the moment in the west a large number of people don’t see any moral inequivalancy between homosexual and heterosexual relating, so in order for such a drug to be even available and offered we’d need a huge paradigm shift for the public.

  2. I would take the pill, but I don’t think taking it or not makes a difference when it comes to our life with God. All lives are equally valued by God – no matter what one’s genetics, handicaps, circumstances, etc. The born or bred pedophile, the child born into a family of thieves or into poverty, the Hollywood child, the severely handicapped – I believe God makes his salvation available equally to all, though it may not seem so to us. What God calls us to do is live according to His teachings, no matter what our impediments.

    So we take this pill not to bring us closer to God, but for our earthly comfort and convenience. Obviously, there is nothing wrong with this – we make similar decisions every day.

    A good analogy here, I find, is with deafness. Some in the deaf community wouldn’t take a ‘hearing pill’ because they’ve become so attached to deaf community and culture. If it were me, I would take the pill, but the decision not to take it is neutral from the religious perspective, I think.

    People might think it cruel of parents not to give their newborn deaf child a hearing pill. Is it cruel for poor parents to have children? Even just one child? It depends, no?

  3. The interesting thing for me that both Peter and Saul’s responses raise is my sense that my being gay is not something that I would change. There is something very powerful in the gift of my sexuality which has enabled me to encounter God and other people in exciting and creative ways.

    In my continuing aware of my difference, I have been constantly drawn to engage with people and ideas that do not fit well into the ‘norms’ of society. There is something liberating in standing with all those who in some way ‘queer’ the hegemony of patriarchy, of power and of oppression in all forms. In some senses, this is something that enables me to stand in solidarity with Christ who ‘acts up’ in order to subvert the values of those around him.

    If it were not for the gift of being gay, I am not sure that I would ever have discovered this – that I would remain trapped in the blindness of earlier times.

    I suppose this is something that I was trying to hint at earlier. Is there something about being gay, about being at the edge of norms that would be lost if people like me disappeared. As Saul states, you could say something about ‘deaf’ people, but I guess I cannot see how many people would want to remain in their ‘deafness’ in the way that I believe people are wanting to delight in the gift of their homosexuality. It is interesting that there are now some teenagers who are having very few negative experiences in their embracing of their gayness – who look at their heterosexual peers and do not experientially feel too different. Conversely though, this could be a worrying phenomena in that such gay young people may too easily become apathetic to those whose voices are not easily accommodated still today.

    • I wonder though whether those of us who have been at the sexual periphery do still hold onto that sense of “queer” in our continuing pastoral care. I for one am not shocked by anything that people bring to me and I think part of that is having experienced being one of those who for others was “shocking” (yes the traditionalist church is still in large parts homophobic). I’m not sure though that “remaining gay” necessarily makes one more open to that.

      • For me though, embracing being ‘queer’, standing in solidarity with those who are also on the edges, who deviate in some way from the norms of patriarchy, is not supremely gift because it enables me to accept others – to not be shocked. Not that this is a bad thing, and I am sure you are right Peter about yourself. However, it is gift because it forces me to recognise that the voice of God is to be found reverberating in the lives of the displaced and marginal. In doing this, it forces me to move out beyond what my narrow vision tells me is authenticate and to re-vision what God might be doing in those that I encounter. It enables me to see that what God did for me, he is doing for others.

        Ultimately, if I were to talk about vocation, I think that this is the role that gay people have to play out in the Church today – they have to remind us all that ‘difference’ is at the heart of God and of his creation. That God, who is difference in unity, is constantly pushing back out our boundaries in which we have sought to imprison love within our limited structures.

        Of course, I am not suggesting that difference is intrinsically good; the risky and difficult business is the discernment that is needed in order to authenticate whether or not each successive re-envisioning is of the Spirit. Invariably though, there always have to be an awareness that those doing the discerning are usually those who have the most to loose if the boundaries move.

        There is a lot of these ideas in the works of Lisa Isherwood, Elizabeth Stuart, James Allison and Robert Goss.

  4. Just to throw fuel to the fire, I just wanted to emphasise that the fruit fly study demonstrates that homosexual behaviour can be influenced by externally applied chemicals, it says nothing about orientation (despite the last sentence of the piece quoting one of the investigating scientists). How do we know what a fly is feeling as it mounts another? As Peter commented in an earlier response, sexual activity in these flies is read as on par with sexual orientation, but the study does not demonstrate orientation only the outward practice of the fly. Human sexuality is very complicated, and though this study is interesting, it is not scientifically rigorous to extrapolate the results to the human experience of sexual attraction since it doesn’t actually contribute to this discussion. However, it is very interesting to follow the conversational threads that this publication has motivated!! Keep talking about it!

  5. I brought up deaf people because I had actually heard of a deaf couple who wished their child would be deaf. Oh, wait, here’s a link with more – I’m not doing it justice.

    ‘…difference is not intrinsically good.’ I agree entirely.

    Of course, one could make up a story that this difference and acceptance is the Holy Spirit’s way of leading us. It’s a nice story – I’m not saying it’s false – it could be true – but it’s essentially a new religion/philosophy. And what happens to once the pill become available, so to speak? Same issues remain.

    One way of looking at it is that we have knowledge today that some think negates fundamental aspects of Christian tradition. Clinging to what there is left of Christianity, we can say that it is the Holy Spirit enlightening us. Those who’d rather not cling will relegate the whole idea of Christianity as having been a quaint but obviously false story. What with the resurrection and all…

    Then there are those of us who have faith in orthodox Christianity…Eve Tushnet’s piece at the bottom of the page.

  6. I am not convinced what I am saying is a ‘new religion/philosophy.’

    The tradition is deeply subversive if we scratch at the surface – the problem is that often western, european men have sought to push it down in order to exult their versions of ‘orthodoxy.’

    I believe in ‘orthodoxy’, just not the present version of it.

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