Genetic and Environmental Causes of Homosexuality

Introduction

Homosexuality has been a debatable topic for hundreds of years. People have been questioning the entire concept: why people are this way, how they deal with daily life, and what goes through their minds. Researchers and philosophers have tried to decode the characters who live through this phenomenon. Many people only associate sexual orientation with sexual attraction, but sexual orientation usually indicates intimate feelings, attraction, arousal, fantasy, and temptation. Different faiths (i.e., Christianity, Judaism, Islam, Hinduism) consider having relations with a member of the same sex to be sinful. These religious communities commonly have a hard time accepting this group of people because it is against what they believe. For example, in the Torah, it states that “if a man lie with mankind, as with womankind, both of them have committed abomination: they shall surely be put to death; their blood shall be upon them” (Leviticus 20:13, King James Version). Those who are homosexual and followers of one of these conservative religions will sometimes try to deconstruct their sexuality and become straight because of the shame. Some people have even turned to conversion therapy to reverse their sexuality to heterosexual as opposed to gay or bisexual. There have been medical approaches attempting to “cure” homosexuality by using ways like castration, injection of various hormones, electroconvulsive shocks, and even lobotomy. Before 1975, homosexuality was considered morbid in the United States, but in some places like the Middle East, it still is. Homosexuals and their supporters have publicly been fighting for equality in the United States since the early 20th century. Although most LGBTQ+ equality activities have been in the United States, there are also people in this category from non-Western cultures and areas. There are different levels of sexual orientation. In 1948, Alfred Kinsey, “the father of the sexual revolution,” created a seven-category scale that represents various degrees of sexuality, running from 0, being exclusively heterosexual, to 6, being solely homosexual. In between those numbers are different levels of bisexuality (Kinsey et al., 1948).

Genetic and Environmental Causes of Homosexuality

Researchers have come up with many different theories as to how someone becomes gay. Some propose it is purely biological and others believe that the surrounding environment affects sexual orientation. There is no solid proof of what the real reason is, but theoretical evidence pools together to give scientists an idea so they can pursue further research. The concept of sexuality cannot be analyzed as it exists at many different levels – chromosomal, genital, brain, partiality, gender self-image, gender role, and a variety of subtle influences on behavior. Although genetics could play a minor role, societal impact and environmental factors, such as exposure to hormones in the womb, mainly influence sexual orientation.

There are many different possibilities of genetic impact on sexuality, as “variation in any trait is accounted for by the influence of genes” (Hamer, 1993). Dean Hamer, an American geneticist, has been researching the role of genetics in sexual orientation for 30 years. He has linked the Xq28 chromosome band to homosexuality in males. In the 1990s, Hamer conducted a study in which he found that homosexuality is a trait inherited genetically through the maternal line of DNA.

Scientists are also trying to link functions to structure in regards to brain use. There have been many studies focusing on the brain chemistry of people with various sexualities and in one study, “Yale scientists found that women used regions in both their right and left brain cortices in certain instances, while men used only the left side” (Gur et al., 1999). This means that there is a possibility that there are differences in the mentalities and behaviors that contribute to homosexuality. The answer to this research is far from clear, but there is also a theory that cell count affects sexual orientation as well. American-British neuroscientist Simon LeVay found that the hypothalamus of a homosexual contained twice the amount of cells than that of a heterosexual person. Similarly, another nucleus, INAH-3, is twice as large in a heterosexual as in a homosexual. The meaning of these facts is unclear, but if scientists uncover what this means, then there could be a breakthrough in sexuality research. There would be a better understanding of the differences in brain chemistry depending on sexuality (LeVay, 1991).

There are many influences said to be made by society in sexual orientation, such as a person’s childhood and family. “Some try to argue that homosexuality follows traumatic childhood experiences such as rape and molestation” (Bailey et al., 1994). For example, a young girl raped by a man could become repulsed by men and their sexual organs and become a lesbian. Similarly, a boy molested by a male could become attracted to the same sex because he found satisfaction in the molestation. There is also a possibility of PTSD after living through these traumatic events that affect your mental state and changes preferences or behavior.

There is support to the claim that young boys who have a distant, non-attentive father and have overprotective mothers could become gay. The boys remain tied to their mothers and never connect with their father, losing their masculinity along the way. The boys turned adolescents seek to find a same-sex love or connection that they failed to have during childhood to fill that gap. There is a psychological process in early life when everyone establishes their sexuality, and these relationships significantly contribute to that.

The fraternal birth order effect is the observation that the more elder brothers a man has, the higher the probability is that he will be homosexual. Twenty years ago, sexologist Ray Blanchard founded this concept. He had found that for every older brother a male had, the probability of homosexuality would rise by 33%. Multiple studies confirmed this hypothesis by testing over 10,000 subjects. 20-30% of men showed to credit their sexuality to this effect (Blanchard, 1997).

“Research suggests that hormonal influences during fetal development may impact certain parts of the brain and in turn impact sexual orientation” (Ellis & Ames, 1987). As the embryo develops, the sex-related genes are turned on and off as the hormone levels in the mother’s womb fluctuate. These hormone levels, produced by both mother and unborn child, benefit the child by continuing steady growth. This exposure is credited for masculinizing genitals and brain structure. This testosterone affects the physical ability and the masculinization of a variety of traits. The epigenetic changes may cause homosexuality in the child’s future children. This homosexuality happens in not only humans but the entire animal kingdom. There has not been a species in which homosexuality has not been shown, for the exception of asexual organisms.

In 2012, William R. Rice, a professor at UCSC, and his associates suggested that epi-marks might lead to homosexuality, passed from father to daughter or from mother to son. These marks influence the unborn child’s sensitivity to testosterone in the womb and may lead to a change in brain chemistry. This sensitivity leads to a possible same-sex attraction (Rice et al., 2012). There is a question of ‘if one twin is gay, then why is the other twin not automatically gay as well.’ If Rice’s hypothesis is correct, the mother’s epi-marks erased in only one son. Neither of the twins may have inherited any of the epi-marks, but one picked them up in the womb, and that influenced their sexuality. It ultimately means that the origins of sexual orientation are found in the interactions among the sex hormones and the developing brain.

Sigmund Freud introduced the concept of the Oedipus complex, positive and negative, which the ‘positive’ is referring to a child’s unconscious sexual desire for the opposite sex parent and a hatred for the same sex parent. The ‘negative’ is when the child is attracted to the same sex parent and loathes the opposite sex parent. Freud believed that if the negative Oedipus complex were to take place, then it could lead to pedophilia or homosexuality. “In pre-oedipal homosexuality, the libido failed to enter the oedipal phase, and simply remained stuck for a lifetime in the early homosexual phase” (Freud, 1920). For instance, when a man enters a sexual relationship with another man, he psychologically reestablishes the oedipal bond, but oppositely.

Conclusion

Although there are many plausible reasons, there is no one exact cause of homosexuality. Researchers are investigating the various genetic and environmental possibilities. There is not a single cause for this concept, but there are many biological and social factors. It could be a mixture of inherited DNA, like the Xq28 chromosome band that males receive from their mother, or it could be a childhood experience: traumatic or being in a certain parental situation. If scientists find the exact cause of this phenomenon, the question of millions will be answered.