The science of human sexuality, as with anything to do with our intriguing and sometimes infuriating species, is complex. Undisputed answers as to the exact biological reasons why individuals can be sexually attracted to people of the same sex as themselves, to persons of the other sex, or to people regardless of their sex, are few and far between.
What does emerge clearly throughout the research is the extreme interdisciplinary nature of trying to understand human sexuality and maybe here, science needs to take a leaf out of sexuality’s book: to catch up and accept the evidence that people sit in a much broader spectrum than given credit for.
What we do know beyond a shadow of doubt, however, is that our preferences are often hard-wired into our bodies – they are not purely psychological and, far less, a “lifestyle choice” – a deeply misguided meme for which Sigmund Freud has much to answer.
The spectrum of human sexual experience is vast, and its incredible diversity is not always acknowledged.
In this review of the current science we have tended to generalise (and for that we apologise), referring to “gay”, “straight” and, less frequently “bisexual”. The science itself often speaks in these simplistic terms, but people do not form such well defined blocs in their gender traits or their attraction to others – nor indeed in the gender they self-identify as.
As geneticist Sophia Frentz says: “What matters is that we do our best to minimise the impact our previously held values have on the science that is being done, and to ensure that that research is not only being done for good reasons, but reflects or at the very least acknowledges the community that currently exists.”
There are those who believe that science should take a back seat in discussions of sexuality. Some fear that the isolation of a “gay gene” (or genes) could lead to selection against foetuses carrying it, while some scientists question whether time and effort would not be better spent elsewhere.
“Homosexuality is not a disease, it’s part of natural human variation. I think we’ve reached the point that we have enough evidence that there’s a biological basis for sexual orientation,” Margaret McCarthy, a neuroscientist at the University of Maryland told The Scientist.
That may be true, but we should also never underestimate the power of science to guide wider social trends. In 2007, during the heated debates In Singapore over whether or not to repeal the law making sex between men a crime, the country’s conservative leader Lee Kuan Yew, never previously known for his sympathy for the gay community, stepped into the fray with his unexpected support for decriminalisation.
“If in fact it is true, and I have asked doctors this, that you are genetically born a homosexual…you can’t help it. So why should we criminalise it?
“They are born that way and that’s that. So if two men or two women are that way, just leave them alone.”
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