Summer II Group 3: The Gay Gene - Natural Homosexuality


For as long as life has existed, so has homosexuality. It can be identified among most species of animals around the world, but the social and religious norms of humans have cast homosexuality into a negative light. However, in some societies homosexuality is accepted, even celebrated. And, in some societies, homosexuality isn’t even acknowledged.

Where did homosexuality originate? Controversy has raged for years as to whether or not homosexuality is a result of nature or nurture. This article explores the idea that homosexuality is in fact a product of nature, possibly even being a product of a mysterious ‘gay gene.’

Introduction and Background


Psychologists and scientists have been studying the tendencies of men and women for years searching for the cause of homosexuality. Scholars have taken many different approaches to the mystery, for example the idea of gay genetics. It is the debate of nature versus nurture, with studies ranging from brain tests to family tree analysis.
Although the genetic theory currently presents itself as the strongest, many still disagree and endorse other causes. Of the many who disagree, few settle on the same contradiction to homosexual genes. Some of the other most prominent theories are dissected and explored in the following sections.

What is Homosexuality

Princeton University defines homosexuality as “a sexual attraction to (or sexual relations with) persons of the same sex.” This definition can also be extended to include a sense of self and social identity. Just as other traits, homosexuality can give membership to a community of similarly defined people. Although sexual orientation is often described as continuous spectrum, homosexuality is one of the four ‘main’ categories: homosexual, bisexual, heterosexual, and asexual.

A History of Homosexuality

Homosexuality is a feature of humanity that is as existent in ancient society as it is in the modern day. As described by Bidstrup in 2001, homosexuality is “very commonly practiced in nearly every culture, whether tolerated or not. The only difference in the openness with which it is practiced.” For example, many Christian churches deny that homosexuality was ever tolerated, possessing an extremely opposing attitude towards the practice today.

Knowledge of homosexuality exists in Prehistoric Africa. Although knowledge is limited, early references through the Brazil Inquisition prove that the practice did in fact take place, and with a slowly evolving culture, likely long before the recording. In fact, enough references have been recorded to use homosexuality as “a justification for considering African cultures primitive enough to justify slavery.”


Ancient Greeks and Romans were also known to regularly practice homosexual acts. Homosexuality was not only existent in these two cultures, but in fact extremely common. Although modern anti-homosexual organizations try to show that homosexuality was prosecuted, “the fact is that no surviving account of prosecution for a homosexual relationship, prior to the Christian era, survives.” (Bidstrup, 2001) However, their tolerance for homosexuality fell alongside their empire when Emperor Constantine “converted” to Christianity.

Homosexuality in North America has been traced back all the way to the Native American’s themselves. A term “Two Spirit” (a proposed replacement for the previously coined term ‘berdache’) was used to describe spiritually gifted men that typically dressed as women in a tribe. These leaders were responsible for keeping ancient stories alive, and spiritual acts and traditions involved for the tribe. The “Two Spirits” were also recognized, according to Bidstrup, as possessing the “special gift of being ‘between genders.’”

One of the earlier modern accounts that adopted more accepting positions on homosexuality was that of Havelock Ellis. In 1901, Ellis “argued that homosexuality was inborn and therefore not immoral, that it was not a disease, and that many homosexuals made outstanding contributions to society.” (Herek, 2009) The concept of homosexuality being inborn became a means for the church to chastise and shun homosexuals from being proper members of society, but Ellis tried to reason otherwise. Ellis believed nature was the responsible party for homosexuality existing.

A different psychoanalyst by the name of Sigmund Freud argued a different point around the same time as Ellis. Freud believed that “humans beings were innately bisexual, and that they become heterosexual or homosexual as a result of their experiences with parents and others.” (Herek, 2009) Whereas Ellis presented the argument that nature was the cause, Freud was not suggesting that nurture may be the root of homosexuality. This controversy would last until the modern day, where researchers still struggle to find deterministic evidence for either side.

What Freud and Ellis both agreed on, however, was that sexual orientation was not a sickness or a trait that would necessarily degrade that person’s role in society.

“Homosexuality is assuredly no advantage, but it is nothing to be ashamed of, no vice, no degradation, it cannot be classified as an illness; we consider it to be a variation of the sexual function produced by a certain arrest of sexual development.” -Sigmund Freud, 1935 letter

As this letter was to an American mother worrying about her child, he continued to write that “Many highly respectable individuals of ancient and modern times have been homosexuals.”

In November of 1950 a large step towards homosexual recognition was taken by the founding of the first homosexual political organization in America: The Mattachine Society. (Western Michigan University) This society became particularly famous and gathered a lot of support when Dale Jennings (one of the founders) was arrested in 1952. His charges were the vague notion of “lewd and dissolute behavior”. This trial was notable because he publicly announced his homosexual in court, thereby forcing the court to separate what was defined as illegal and homosexual. In the end, his charges were dropped.

In 1957, Evelyn Hooker conducted a study in an attempt to find correlation, or lack thereof, of homosexuality and certain aspects of a person’s psyche. She recruited a large number of heterosexual and homosexual men that were functional in society, and put them in front of a series of experts that would rate their adjustment to society. However, the experts she recruited did not have any knowledge of the sexual orientation of the gentlemen they analyzed. Hooker found that there were no differences in societal adjustment level between the two orientations. She described it as ‘homosexuality is not inherently associated with psychopathology.’ (Herek, 2009)

Homosexuality has been present for a long time, and many studies have been performed. Many studies have concentrated on the existence of specific elements of human physiology that could prove homosexuality is in fact a natural occurrence.

Genetic Evidence for Homosexuality

Discovery of the "Gay Gene"?

A 1993 study conducted by Dean Hamer mentioned in TIME Magazine suggests that homosexuality is a result of nature, also known as biological factors. “The role of genetics in male sexual orientation was investigated by pedigree and linkage analyses on 114 families of homosexual men…The goal of our work was to determine whether or not male sexual orientation is genetically influenced. We used the standard techniques of modern human genetics, namely pedigree analysis and family DNA linkage studies.”. (Hamer, 321) Specifically, homosexual twin brother’s with a history of homosexuality on the mother’s side were studied. In these homosexual brother’s genes, on the chromosome inherited from the mother, the X chromosome, a distinctive pattern was found along a specific segment. These findings suggest that at least one gene on the X chromosome may contribute homosexuality in men.


Genetic Alteration

In a different study, Korean geneticists altered the sexual preferences of a female mouse by removing a single gene. This gene, referred to as FucM (short for fucose mutarotase) is linked to reproductive behavior. Those females without this gene avoided male mice, declined to sniff male urine, and made passes at other females. Chankyu Park, of the Korea Advanced Institute of Science and Technology in South Korea says that the absence of the gene tricks a female’s brain into functioning like a male’s brain. A similar study performed in 1995 by the National Institutes of Health found that the removal of a specific reproductively linked gene caused bisexuality in male fruit flies. (Popular Science) These studies show that genetic alteration is the key to unraveling the mysteries of the “gay gene”.

Homosexuality at a Young Age

In an ABC 20/20 article published in March of 2008, ABC interviewed an 18 year old boy named Zach O’Connor. Zach says he knew that he was homosexual from the time he was 5 or 6. "I guess I didn't want to associate myself with guys, 'cause I was like, 'well, I don't want any feelings to happen,'" he told us. "'So I'll associate myself with girls."(ABC) Zach didn’t know why he was different; he just knew he liked boys. He says he didn’t develop romantic feelings for other boys until he hit puberty at around 11 years old. Another boy, named David Hawkins, was signifying feminine traits as young as 3 years old. His parents were convinced of his homosexuality through his feminine traits, “prissiness”, and flamboyant mannerisms. These instances in which people realize or demonstrate that they are homosexual from a very young age contributes to the belief that homosexuality occurs genetically. No child would purposely ostracize themselves from other children; which proves that in these instances, homosexuality is not a choice, but is genetically marked within them.

Physiological Differences

Physiological differences between homosexuals and heterosexuals also support the idea that the answer to homosexuality lies within genes. Homosexual men report slightly longer and thicker penis sizes than heterosexual men. Homosexual men and heterosexual women have, on average, equally proportioned brain hemispheres while homosexual women and heterosexual men have, on average, slightly larger right brain hemispheres. Homosexual men’s brains respond differently to antidepressants, such as Prozac. A study of 50 homosexual men found 23% had counterclockwise hair whirl, as opposed to 8% in the general population. Also homosexual men and women are 50% more likely to be left handed or ambidextrous than heterosexuals. These are only a few of the differences founded by research.

Alternative Scientific Studies and Rebuttal

Brain Studies


Among many other commodities of the body, the brain has been studied to attempt to determine a correlation between the attributes and function of ones’ brain to homosexual tendencies. One of the most reputable homosexual brain studies was conducted by neuroscientist Simon LeVay in 1991. LeVay examined and compared the INAH3 part of brains of self-proclaimed homosexual and heterosexual cadavers, men and women. The study included 16 heterosexuals and 18 known homosexuals. From his small scale experiment, LeVay found that the brains of homosexual men have much more in common with the heterosexual female brain than with the brain of a heterosexual male. The similarity that presented itself was the size of INAH3 in the brain; the average heterosexual male was twice the size of the other subjects. It was predetermined that the INAH3 of the brain corresponds to sexual behavior but never before sexual orientation. The latter is the connection that LeVay believes he made.

LeVay’s studies, although ground breaking, have been questioned because of the small group of subjects. After his results were published, LeVay did admit that his findings did excuse a few outliers in his data. Also, six of the heterosexual cadavers used in the experiment had died as a result of AIDS, a disease commonly transmitted through male homosexual intercourse. This raises doubts as to whether or not the heterosexual subjects were in fact heterosexuals.

Another less reputable brain study was conducted in 1991 by LS Allen and RA Gorski. Their findings proclaimed that the anterior commissure area of the brain was linked to homosexuality, stating the area was larger in brains of gay subjects. Although these findings are not disregarded, the results have been widely contradicted in other studies.

Homosexuality Influenced by Pregnancy and Hormones

The general debate between nature and nurture was mentioned earlier. This next theory mashes the two together by proclaiming that the sexual orientation of an unborn child is influenced by the conditions of pregnancy. This study’s hypothesis is a credible one backed up by a 2006 study masterminded by Anthony Bogaert. Bogaert researched a group of 944 Canadian men, examining their family trees and with whom each of the men lived with. By studying the subjects’ family heritage and current family life, Bogaert had the possibility of finding social and genetic patterns.
The physiologist discovered that the strongest pattern regarding sexual orientation was the biological birth order of the men. The study indicated that the more biological older brothers a male has, whether they live with one another or not, makes him more likely to be homosexual. This suggests that the presence of a male fetus could change the condition of the womb or affect the mothers’ ability to carry the baby in the fashion as she did with her previous child. Bogaert published that the 3% likelihood of any man being homosexual is increased to 5% if the man has several older brothers.

Bogaert’s conclusion is comparable to the idea that a males hormone levels influence their sexual orientation. Although the hormone level of gay men and women can often be seen as a stereotype, some correlations between the two are evident. Due to the early approaches to the study of homosexual and the typical portrayal of homosexuals in the media, this explanation is often taken as truth. However, evidence has shown that post-birth hormone treatment has not affected sexual orientation which discredits the idea that strictly hormone levels can determine sexual orientation.

Although Borgaert’s research appears flawless, the experiment did not conclude the specific cause of homosexuality. It presents a strong correlation but lacks to offer a specific reason for the trend. Does the womb physically change? Or does the pregnancy differ? Or is this correlation a mere coincidence? Homosexuality could have a genetic link dealing with the fertility of a mother. Socially, men could feel more comfortable admitting their sexual orientation in areas that also happen to embrace having large families.

Environmental Influences

Social Psychologist Daryl Bem of Cornell University presents an interesting environmental theory. Bem’s presented his concept in the 1996 publication of “Exotic Becomes Erotic: A Developmental Theory of Sexual Orientation.” The journal article explained Bem’s belief that sexual orientation is a product of ones’ interactions and views of different genders. If a boy or girl feels very different from other kid of their gender for whatever reason, they begin to view that gender as unusual or even bizarre, or what Bem dubs it, exotic. This feeling of exotic leads to “produces heightened nonspecific autonomic arousal that subsequently gets eroticized to that same class of dissimilar peers.” (Bem 1)


Similarly, those who believe that being gay is a combination of genetics and environment argue that things like hormone levels cause a child to be unique and that it is not their hormone levels but rather their uniqueness that ultimately persuades them to be a homosexual. A hormone level, or the womb bearing the fifth biological son a family has, is merely the assist to the environment that shapes a person.

Assist or no assist, some claim the cause of sexual orientation is purely environmental. Proponents of this theory often cite factors of early childhood development and the parental situation as chief influences of sexual orientation. Furthermore, studies have shown that men who experienced homosexual abuse as a child are more likely to be homosexual or to be sexually attracted to children. The physiological abuse caused by sexual abuse promotes the idea of an environmental cause. However, it is more than doubtful that the majority of gays have experienced something as devastating and lasting as sexual abuse

Cultural Factors

One of the main reasons homosexuality is so difficult to study is the negative connotation that our society has labeled it with. Case specific, when people realize and choose that they are homosexual, the next immediate step is not to proclaim it but rather to decide whether or not to admit it to themselves and their peers. Because of that, it is hard to study homosexuality causes due to the fact that the dependent variable of the experiment must decide to first admit the result before they can be recorded.

Cultural factors play a role in declaring homosexual orientation. Homosexuals are more common in urban settings and in areas with higher levels of education. Both play large roles in tolerance, and tolerance plays a large role in the proclamation of homosexuality.


The ultimate goal of this article is to demonstrate all of the variables effecting sexual orientation through the examples provided above. What most people do not understand is that genetics are extremely complex and multiple factors contribute to specific traits. "Since sexual orientation is such a complex trait, we're never going to find any one gene that determines whether someone is gay or not; it's going to be a combination of various genes acting together as well as possibly interacting with environmental influences." (WebMD) This means that there are enormous possibilities in factors effecting sexual orientation. There is no such thing as a pinpointed “gay gene,” but there are plenty of possibilities as to the combination of factors contributing to this condition. But the existence of a natural influence of homosexuality is hard to deny. Nature is a powerful force, and is still operating in mysterious ways.



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Herek, Gregory M. “Facts About Homosexuality and Mental Health.” University of California-Davis. 2009. Web. 10 Aug. 2011. <>

Bidstrup, Scott. “Saint Aelred the Queer. The Surprising History of Homosexuality and Homophobia.” 2001. Web. 10 Aug. 2011. <>

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Anna Dellapenta

The only revisions I performed were simple grammar/punctuation/word choice modifications.

I enjoyed this article because it was exceptionally detailed while it maintained readability. The pictures were also a very nice touch, especially when used in combination with frequent subheadings and short paragraphs.

The "Alternative Scientific Studies and Rebuttal" section was fascinating to me because I am very familiar with the topic and I had never heard of most of the things you mentioned. That being said, I think the "Cultural Factors" part of this section was written as if it belonged somewhere else in the article. It describes how cultural factors cause the difficulty associated with studying gays and how cultural factors affect people "declaring" themselves as gay. The other parts of this section focused on other causes of being gay.

This last comment I probably only noticed because I'm a lesbian but this article mentions gay men and studies on gay men a lot more than gay women.

Alexis Carambot

This article was very well written and included much detail. The way the information was presented was orderly and flowed well. I liked how they took the different angles of the controversy and justified them all. For the revisions I would have change some of the wording and sentence structures.

Shan Rammah

Of all the groups’ topics, this one is my favorite. Both sides were presented well, and the facts were clear. The only thing I disliked about this paper is that it did not touch on the psychological aspect of homosexuality. There is a common notion among people who don’t know much about homosexuality that it is a mental disorder that needs to be cured. But when you look at the facts, these groups listed below all agree all that homosexuality is not a mental disorder (APA).

• American Academy of Pediatrics
• American Association of School Administrators
• American Counseling Association
• American Federation of Teachers
• American Psychological Association
• American School Counselor Association
• American School Health Association
• Interfaith Alliance Foundation
• National Association of School Psychologists
• National Association of Secondary School Principals
• National Association of Social Workers
• National Education Association
• School Social Work Association of America

"Just the Facts about Sexual Orientation & Youth: A Primer for Principals, Educators, & School Personnel." American Psychological Association (APA). Web. 13 Aug. 2011. <>.

Greg Kubacki

I found this article to be a little difficult to follow and read. Some grammatical errors do make it a little difficult and the flow caused me to have to re-read things a few times. Jumping back and forth between ideas and theories makes the article difficult to follow. You also never really took a clear stand on the controversy. Nature or nurture? Some of the experimental results could have also been explained better to more effectively convey the meaning behind the results of the experiments. For example, the findings that the later male births are more likely to result in a homosexual child, this could have been accompanied by a more in depth explanation as to why the findings were not a mere coincidence. Overall this was a fun read for me because I know a few homosexual people and it is always interesting to learn new things about it.

Justin Emery

Over all I really liked the article, it tries to answer the fundamental question of why; which any homosexual person being raised in a conservative christian home whats to know the answer to. Over-all I liked the flow and while it does not go in very very specific detail it gives a general over view which can peak a persons interest to do a little more research on their own. The only thing that bothered me, not in a I am pissed off way but more of a sigh…, was the sentience "died as a result of AIDS, a disease commonly transmitted through male homosexual intercourse", that sentence just reinforces the stereotype that aids is a "gay" disease and it was put here by God to punish those who live in sin to quote people at my old church; but that is a controversy for another wiki article.

Patrick Black

I think you guys really picked a good topic to discuss here. I like the high level of controversy and overall I think you did a good job of addressing all conditions that may affect sexual orientation. The key here to support your claims from my perspective is to use a combination of the two accepted theories: nature v. nurture. Neither source of social development can truly be pinpointed to be the determining factor, but rather how the conditions interact to create the complex trait of sexual orientation. Social development doesn't start in the womb, but the conditions that are developed at birth will certainly affect the personality of the individual. Fundamentally, homosexuality is a normal occurrence. It is irregular, but in nature there are many normal occurrences of irregularities that serve no disadvantage. Human homosexuality is no different.

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