Is being gay genetic or environment

Homosexuality was considered a mental illness when Richard Pillard was in medical school. It was the s and the School of Medicine professor of psychiatry was at the University of Rochester. At the time, the American Psychological Association still listed homosexuality as a disorder and psychologists and psychiatrists were trained on ways to treat it.

The first psychological test undertaken to determine whether there was a biological explanation for homosexuality was in With a grant from the National Institute of Mental HealthKaren Hooker studied the relationship between homosexuality and psychological development and illness.

Hooker studied both homosexuals and heterosexuals—matched for age, intelligence, and education level.

Nature vs. Nurture: The Biology of Sexuality

Hooker found no major differences in the answers given by the two groups. Because of the similar scores, she concluded that sexuality is not based on environmental factors. There have been numerous studies designed to determine whether or not homosexuality has a genetic cause.

Among the most notable were a series of studies Pillard and J. Michael Bailey, a professor of psychology at Northwestern University, conducted in the early s that found that homosexuality is largely biologically determined, not environmentally influenced.

Pillard and Bailey examined identical and fraternal twin brothers—as well as nonrelated brothers who had been adopted—in an effort to see if there was a genetic explanation for homosexuality. They found that if one identical twin was gay, 52 percent of is being gay genetic or environment time the other was also; the figure was 22 percent for fraternal twins, and only 5 percent for nonrelated adopted brothers.

Pillard is quick to point out that much about how sexual orientation is determined remains a mystery. And the answer is: not a lot. BU Today : Has your research found that sexual orientation is biologically determined? Pillard: I think so. But nobody knows for sure what causes a person to be either gay or straight.

What we did was to recruit groups of twins, identical and fraternal twins. And the theory is if a particular trait is genetic, the identical twins would be more alike than the fraternal twins. The results were that they were more alike. The identical twins were far more similar than the fraternal twins.

Is there evidence that life experiences play a role in sexual orientation? And how do you know the mother really was overprotective—you have to depend on what the subject in your study is remembering about his early years. And that could be easily falsified. Your research suggests that there is often a familial pattern in homosexuality.

It seems to us that being gay runs in families much more frequently than you would expect by chance alone. What made you decide on this research? What was your motivation? Well, because there are so many gay people in my family, including me. It just seemed like a logical thing to do.

At the time that I was searching for a problem, that popped out. I think that the future of this kind of research belongs to people who are geneticists, people who are expert in gene mapping. These are the sort of bench scientists, where I am more interested in clinical things.