Massive study reveals there is no gay gene

The big reveal: The study used the UK Biobank containing thousands of adults’ DNA.

Are experiments like this harmful? Human sexuality is far more complex than previously thought, say scientists. But some in the LGBT community say the research should never have taken place.

Twenty doctors from 21 institutions analysed the DNA of almost 500,000 people in Europe and the USA. They wanted to find out once and for all whether a “gay gene” determines a person’s sexuality.

“This is approximately 100-times bigger than previous studies on this topic,” said Andrea Ganna, a Harvard scientist who led the research.

They found that genetics accounts for roughly 8 to 25% of variation in sexuality. The rest may be determined by conditions in the womb or environmental and social factors later on, but human sexuality, overall, remains a complex mystery.

There are “thousands of [genes] scattered across the genome, each [will] have a small influence on same-sex sexual behaviour”, said Harvard scientist Benjamin Neale. However, “that implies it will be effectively meaningless to predict an individual’s same-sex sexual behaviour from genetics”.

The scientists highlighted five genetic variations particularly associated with having same-sex partners. One of the genes is linked to smell, and the others to sex hormones. Strangely, they also found that different genes seem to influence male and female same-sex desire.

All this evidence suggests that sexuality is on a fluid spectrum, rather than it being a binary division between “gay” and “straight”.

The new findings debunk the “gay gene” theory, which first emerged in the 1990s after a study suggested there was a single genetic switch for homosexuality. Its results were never replicated.

Since its inception, the theory has been used as fuel for bigotry. In 1993, The Daily Mail published an article under the headline: “Abortion hope after ‘gay genes’ findings”.

The fear that scientific research into sexuality could lead to an attempt to “cure” LGBT people has never gone away. Indeed, some scientists think this latest study should never have taken place.

“Same-sex behaviour is not a disease,” says geneticist Steven Reilly. “When we live in a world that has discrimination against vulnerable populations, we have to ask who does this research potentially benefit and who does it potentially hurt?”

Neale (who is gay) disagrees. “Better understanding of things like same-sex sexual behaviour can lead to stigma reduction. It’s natural and normal, and there’s no genetic test for this,” he argues.

Are experiments like this harmful?

Playing with fire

By treating sexuality as a disease for research, scientists are encouraging society to think of queer sexualities as abnormal and fixable. In fact, homosexuality is common and natural. Besides, as this study shows, there is very little science has to tell us on the matter. It is a dangerous path that should end here.

But others, like Neale, argue that a better scientific understanding of sexuality leads to more awareness and acceptance in the general population. For example, this study suggests that sexuality is fluid and complex — a view shared by LGBT rights activists and a rapidly growing number of young people.

You Decide

  1. Should scientists stop researching sexuality?
  2. Have LGBT people achieved equality in 2019?


  1. Find out the answers to the following questions: Who discovered DNA, and when? Where in the body can you find DNA? What is a chromosome, and how many do humans usually have?
  2. Split the class into two groups and hold a class debate on whether or not should scientists research sexuality.

Some People Say...

“Sexuality is the lyricism of the masses.”

Charles Baudelaire (1821-1867), French poet

What do you think?

Q & A

What do we know?
Young people today are far less likely to identify as heterosexual compared to previous generations. According to a YouGov survey this year, 75% of 18 to 24-year-olds in Britain identify as heterosexual — down from 83% four years ago. Some 16% now self-describe as bisexual, which is 14% higher than in 2015.
What do we not know?
What determines a person’s sexuality. This new study suggests that thousands of genes may play a part, but that is far from the whole picture. Environmental factors, which are believed to influence sexuality, can include factors as broad as what happened to a foetus in the womb, a person's social circle, and where they grew up.

Word Watch

Twenty doctors
They also worked with 23andMe, a genetic testing company that offers services that let people learn about their family history and health from their genetics.
Characteristics that are passed down through generations in your DNA.
When something is made up of just two options.
Starting point.
Prejudice and hatred against certain minority groups.
In the past, this term was used as a homophobic insult. It has now been largely reclaimed by the LGBT community that uses it to refer broadly to sexualities and genders that are not heterosexual and cis-gendered. This can still be a sensitive word, depending on who is uses it and their intent.



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