Between two and six percent of the population identify as being homosexual. There are many political and social theories as to why, but what does the actual science suggest?
Is being homosexual genetic, and do we all hold the gay gene?
In two studies from the 1990s, using the Human Genome Project, researchers found that gay people have a higher number of gay relatives than heterosexual men and that gay siblings have a similar link on their X chromosome, showing a high level of genetic inheritability.
A recent study of 409 gay siblings showed the same X chromosome link as in 90s studies. They named it Xq28. And in another brain region, they found it in chromosome 8.
Additionally, a study from 2014 analyzed from the last 50 years of research of gay men and women are more likely to have siblings that are also gay, suggesting the traits are genetically linked and passed down.
If being gay is genetic, wouldn’t this create a paradox as gay people can’t have children? Gay people do have children but at 80 percent less than a heterosexual. So, therefore, wouldn’t the genes not be passed down and eventually die out?
A recent study from UCLA used epigenetics to propose that everyone carries the gay gene, but it is only triggered and turned on sometimes.
Epigenetics studies how your environment can chemically modify your genes, like how a queen bee’s pheromones can chemically tell the other bees where the hive is.
The UCLA study used both female and male gay twins showing how those specific genes are linked to having a homosexual orientation.
Although a specific gay gene has yet to be found, scientific evidence does suggest that human sexual orientation is linked to genetics and is regulated at the molecular level.
Evidence has shown that giving birth to a son then birthing another son raises the second sons’ chances of being gay by 33 percent. However, no effect is seen if an older brother is from a different mother.
This has led scientists to believe that being pregnant with a male triggers a biological mechanism that affects a mother at birth.
Another study showed that a gay man has more older brothers than the heterosexual population.
Another study showed that when a fetus is in the mother and is exposed to high testosterone levels, they have a higher chance of being homosexual. Why does this happen?
The Gay Uncle hypothesis shows that gay members of a family who don’t reproduce still pass on those genes to extended family members.
Other studies suggest that having the gene gives a person a higher level of compassion, cooperation, and emotional intelligence and lower levels of hostility.
“Homosexuality gives advantages to the group. A society that condemns homosexuality condemns itself.” -E.O Wilson.