Along with proof of cold fusion, photos of the Loch Ness monster or a sure cure for baldness, there’s nothing like the discovery of the gay gene to set the pulse of headline writers racing.
Here’s a few from the last few hours: Boys “turned gay by childhood change in genes” (Irish Independent); “The DNA test 'that reveals if you're gay'” (Daily Mail); “Scientists find DNA differences between gay men and their straight twin brothers” (Los Angeles Times); and “Study: DNA test can reveal male sexual orientation” (San Diego Union-Tribune).
But today’s Hall of Shame Award for Horrible Headlines goes to New Scientist, which ought to know better: “Gay or straight? Saliva test can predict male sexual orientation”.
Here are the facts. Dr Tuck C. Ngun, a gay genetics researcher at UCLA, presented an abstract at the American Society of Human Genetics (ASHG) annual meeting in Baltimore about eight hours ago and will speak to the media today.
He claims that an algorithm using epigenetic information from just nine regions of the human genome can predict the sexual orientation of males with up to 70 percent accuracy. His data was based on saliva swabs from 37 pairs of twins in which one twin was homosexual and the other was heterosexual, and 10 pairs in which both twins were homosexual.
Does this justify headlines about gay DNA? Nope.
First of all, the story is based on an abstract at a conference, not a published paper. Second, the abstract has not been peer-reviewed. Third, the research has not been replicated. Fourth, epigenetics is still poorly understood and it is rash to draw far-reaching conclusions.
In fact, most scientists were deeply sceptical.  Here are a few responses to the news: Dr Ewan Birney, Co-Director, European Bioinformatics Institute: “It is very hard to assess this work from an abstract and press release, and these claims need careful scrutiny. From the abstract, it is unclear whether the scientists have looked carefully at confounding factors, ie, other things which associate with sexual orientation and might be the cause of this correlation.” Professor Gil McVean, Professor of Statistical Genetics, University of Oxford: “Without validation of the result in an independent data set it is not really possible to know whether there is any substance in this claim.” Professor Darren Griffin, Professor of Genetics, University of Kent: “To claim a 70% predictive value of something as complex as homosexuality is bold indeed.  I wait with baited breath for a full peer-reviewed article.” Dr Eric Miska, Gurdon Institute and Department of Genetics, University of Cambridge: “Epigenetics is still a young science and although there is great potential very little is known about the mechanisms that shape the epigenetic landscapes of an individual. Simple correlations – if significant – of epigenetic marks of an individual with anything from favourite football player to disease risk does not imply a causal relationship or understanding.”
In short, science journalists need to be either less gullible or more careful.
Besides, discovering a gay gene is not necessarily good news. If it exists, it can be eliminated. That’s the reason that Dr Ngun has decided to abandon his research. “I just left the lab last week,” he told New Scientist. “I don’t believe in the censoring of knowledge, but given the potential for misuse of the information, it just didn’t sit well with me.”
On the other hand, if it doesn’t exist, is being gay just a lifestyle choice? Michael Cook is editor of MercatorNet.