There’s long been controversy regarding whether our attraction to others is born within us or learned behavior.
Whether there’s actually a “gay gene” has yet to be determined with certainty. Scientists have long suspected that sexual orientation, at least in men, is influenced for the most part by genetics. But they could find no evidence to support that hypothesis. Now, it’s believed, they have what they’ve been looking for. New research seems to confirm a link between sexual preference and DNA tags that can be influenced by the environment.
In a new study of male twins, conducted at the University of California (UC), Los Angeles, by Eric Vilain’s laboratory, it is claimed that chemical modifications of the human genome that alter gene activity without changing the DNA sequence may have a major influence on sexual orientation. The paper was scheduled to be presented October 8 in Baltimore at the annual meeting of the American Society of Human Genetics.
Previous studies focusing upon identical twin pairs have determined that if one sibling is gay, there is about a one-in-five chance that the other will also be. Interestingly, each time a woman has a male pregnancy, the chance that her next son will be homosexual goes up by 33%. These percentages lead researchers to suspect that another factor must be involved.
Now, based upon this most recent information, the argument is moving beyond “genetics or environment” to considering a third option – a sort of bridge between the two. And that area of study focuses upon “epigenetics”.
Epigenetics describes certain tags that may be added to or removed from DNA. They can cause the expression of a given gene to be changed. Simply stated, your DNA sequence must be “read” before proteins can be made…and the tags interfere with the scanning process.
It’s been found that these tags can be affected by environmental factors. And, they’re not necessarily shared by identical twins.
What genes are affected by these tags and what is influencing them has yet to be determined. But this new development is a significant step forward on the long road to finding those answers.
Vilain’s team cautions that their findings shouldn’t be used to create tests for homosexuality or a misguided “cure.”
But psychologist J. Michael Bailey of Northwestern University in Evanston, Illinois, says he’s not worried about such misuse. “We will not have the potential to manipulate sexual orientation anytime soon,” he says. And in any case, he adds, “we should not restrict research on the origins of sexual orientation on the basis of hypothetical or real implications.”