While there is no consensus about the reasons people experience a heterosexual, bisexual, gay, or lesbian orientation, research points to a complex mix of biological factors (genetics, prenatal influences), personality, and developmental experiences.
The American Psychological Association states the following: “There is no consensus among scientists about the exact reasons that an individual develops a heterosexual, bisexual, gay, or lesbian orientation. Although much research has examined the possible genetic, hormonal, developmental, social, and cultural influences on sexual orientation, no findings have emerged that permit scientists to conclude that sexual orientation is determined by any particular factor or factors. Many think that nature and nurture both play complex roles; most people experience little or no sense of choice about their sexual orientation.”
It is difficult to develop theories about the origins of homosexual attractions because no single theory fits every situation. Although there are some commonalities among people, there are no constants. Factors are different from person to person, or at least individual reactions to the same factors vary. Humans are complex beings, and our behaviors are the result of many complex interactions.[1]
Below is a discussion of how personality, biological inheritance, and developmental experiences influence us. As you read these sections, consider how each concept may apply to you.
Personality and Temperament
We all have unique personalities with different likes, desires, dreams, and moods. We see ourselves and the world in different ways and each of us hopes for something a little different from life. One child may be content with the affection he receives from his parents, while his sibling who receives the same attention feels a deficit and requires more. Some children seem content to play by themselves, while others who have many friends seem to need even more.
Many men with same-sex attractions have a heightened sense of emotional sensitivity which can make them vulnerable to emotional hurt when their high expectations are not met. Since we all have different needs and perspectives on life, it is easy to see why two people in the same situation may react differently. For one person, a negative situation may be manageable, while for another it is a devastating crisis.
Biology
Biological inheritance may play a role in influencing behavior or feelings. Some people seem susceptible to certain actions and may be drawn toward them or become addicted to them more easily than other people. For example, one person may be able to dabble with gambling, while another becomes a compulsive gambler. Some may drink only socially, while others have an unusual attraction to alcohol. Studies indicate that genetics may be a factor in susceptibilities to some behavior-related disorders, such as aggression, obesity, and alcoholism. Likewise, there are theories that biological predispositions influence the development of homosexual attractions when other life experiences are also present.[2]
Beyond such predispositions, some scientists have searched for more direct genetic causes—a gene or chromosome that determines sexual orientation.[3] None of these studies has shown any direct genetic cause of homosexuality.
Some studies hint at a genetic or embryological biological component but have not proven that same-sex attraction is an inborn or biologically determined characteristic. The researchers acknowledge that their findings are not conclusive and simply hint at what some of the contributions may be. Furthermore, most of these studies have not been replicated. Sadly, some news reports have misrepresented or sensationalized the facts, leading some people to believe that homosexuality is a genetic trait. The Gay and Lesbian Medical Association recommends that people not use the argument that homosexuality is biological because there is simply not enough evidence. No genetically determined human behavior has yet been found.[5] Most researchers and scientists believe there is no single cause, and that the factors may be different for different people.
The following sections briefly summarize the more significant research in these biological areas.
Twin studies
Eight major studies of more than 10,000 sets of identical twins during the last two decades all arrive at the same conclusion: gays were not born that way. “At best genetics is a minor factor,” says Dr. Neil Whitehead, PhD in biochemistry and statistics.[6]
Identical twins have the same genes or DNA, and they are nurtured in equal prenatal conditions. Therefore, if homosexuality is caused by genetics or prenatal conditions and one twin is gay, the co-twin should also be gay. If both twins are not gay, then homosexuality cannot be genetically or embryologically dictated. “The predominant things that create homosexuality in one identical twin and not in the other have to be post-birth factors.”
Same-sex attraction (homosexuality) is caused by non-shared factors—things that happen to one twin but not the other, or a personal response to an event by one of the twins and not the other.[7]
Chromosome studies
In 1993, news reports claimed that scientists had found a correlation between DNA markers on the X chromosome (region Xq28) and sexual orientation in a selected group of homosexual men.[8] The study suggested the chromosome may play some role in about 5 to 30 percent of gay men. Larger, more recent studies have not found such chromosome associations.[9] See “Not ‘Born That Way’ After All.”
Hormone studies
Studies have shown that in some cases the mothers of homosexual males experienced a high degree of stress during their pregnancy. Since stress affects hormonal levels, some researchers suggest that decreased levels of testosterone could lead to a demasculinization of the developing brain. However, multiple studies over the years have not been able to substantiate the theory, and the available evidence is to the contrary. Ehrhardt and Meyer-Bahlburg wrote, “In the majority of intersex patients with known hormone abnormalities, the sexual orientation follows the sex of rearing. Consequently, we have to assume that prenatal hormone conditions by themselves do not rigidly determine sexual orientation.”[10]
Experiments have been conducted wherein testosterone was given to homosexual males, both those who were effeminate and those who were not. “When there were any behavioral changes at all, the subjects became more like themselves than ever. Their sex drives were usually increased and sometimes their effeminate mannerisms as well (when they had any), but there were never any directional changes in their sexual interests. From these experiments . . . it has become abundantly clear that the sex hormones play a considerable role in powering human sexuality, but they do not control the direction of it.”[11]
Biological conclusions
Regardless of the role that genetics play in the development of sexual attractions, people who experience these attractions can make conscious choices about their behaviors. Although researchers have found a gene present in 77% of alcoholic patients, we know that alcoholics can control their behavior and lead productive lives. You have control over your destiny. You have moral agency and can determine the course of your life.
Drs. Byne and Parsons of the Department of Psychiatry at Columbia University reviewed the biologic theories of human sexual orientation in 1993 and concluded, “[T]here is no evidence at present to substantiate a biologic theory.”[12] No study suggests that a simple cause–effect relationship exists.[13] And Dr. Earl Wilson wrote, “the disputed evidence for physical causes of male homosexuality is even weaker when it comes to lesbianism.”[14]
Of 37 inheritable traits, sexual orientation is the least likely trait. See “How heritable are human traits like personality, height, mental health, physical health, education, religiosity, and conservatism? (h^2 estimates)” at SpencerGreenberg.com/2024/06/heritability.
Also see Homosexuality and the Scientific Evidence at mygenes.co.nz.
Developmental Experiences
Life experiences shape emotional development, self-perception, and how attractions feel or are managed. For some people, these experiences contribute to added distress or challenges.
Summary of Personality, Biology, and Developmental Experiences
Personality (temperament), genetics, and developmental experiences all have a place in influencing our sexual attractions. It is important to appreciate the complexities of sexual orientation and resist the urge to search for simplistic explanations. In addition to any influences of genetics or the environment, the individual plays an important role in determining his or her identity.[15]
Our character grows out of the choices we make and the experiences we live through. Some people are naturally shy, anxious, quick to anger, or prone to dependence. Others struggle with commitment. We usually do not choose these tendencies. Instead, our adult personality develops through a mix of heredity, family influences, and countless small decisions made over many years. Together, these forces create patterns in the way we feel, think, and act.
Will Your Same-Sex Attractions Always Be the Same?
Sexual feelings and attractions can vary in intensity, focus, or manageability over a person’s lifetime for some individuals, due to natural life changes, aging, reduced emotional distress, spiritual practices, accountability, or other personal factors.[17] For example, some report attractions becoming less intrusive, compulsive, or dominant after healing emotional challenges, building healthier relationships, or living congruently with their values, even if core patterns of same-sex attraction persist.
You can gain greater emotional health as you address issues such as those listed in the section “Issues Common Among Men Who Experience Same-Sex Attraction.” The goal is to achieve improved emotional health and a lifestyle aligned with your faith and values.
[1] See Archives of General Psychiatry 42, “Theories of Origins of Male Homosexuality: A Cross-Cultural Look,” pp. 399–404.
[2] See Friedman R. C. and Downey, J. “Neurobiology and Sexual Orientation: Current Relationships,” Journal of Neuropsychiatry 5, 1993, p. 149.
[3] Friedman and Downey, p. 149
[4] See R. C. Lewontin, et. al., Not in Our Genes, Pantheon Books, New York, 1984 and Hubbard, R. and Wald, E., Exploding the Gene Myth, Beacon Press, Boston, 1993.
[5] Whitehead, Neil L. & Briar. My Genes Made Me Do It!, Huntington House Publishers, 2014, 1999.
[6] Ibid.
[7] Read summaries of the results of these twin studies at hollanddavis.com/identical-twin-studies-prove-homosexuality-is-not-genetic
[8] Hamer, Dean, et. al. “A Linkage Between DNA Markers on the X Chromosome and Male Sexual Orientation,” Science 261, 16 Jul. 1993, pp. 325. Also see Hamer, Dean and Copeland, P. The Science of Desire, Simon & Schuster, New York, 1994, pp. 145–46.
[9] Washington Post, 31 Oct. 1994, pp. 5–6. Also see “The Biological Evidence Challenged,” May 1994, pp. 50–55 and Scientific American, “Gay Genes, Revisited,” Nov. 1995, p. 26. See “Genome-Wide Association Study of Male Sexual Orientation,” Sanders, Alan R., et. al., Scientific Reports, December 7, 2017.
[10] Ehrhardt, A.A. and Meyer-Bahlburg, H.F.L. “Effects of Prenatal Hormones on Gender-Related Behavior,” Science, vol. 211, 20 Mar. 1981, p. 1316.
[11] Tripp, C. A., The Homosexual Matrix, McGraw-Hill, New York, 1975, p. 12.
[12] Byne, William and Parsons, Bruce. “Human Sexual Orientation: The Biologic Theories Reappraised,” Archives of General Psychiatry 50, Mar. 1993, p. 228.
[13] Hubbard, Ruth and Wald, Elijah. Exploding the Gene Myth, Beacon Press, Boston, 1993 and “Human Sexual Orientation: The Biologic Theories Reappraised,” Byne, William and Parsons, Bruce, Archives of General Psychiatry 50, Mar. 1993, p. 228.
[14] Wilson, Earl D. Counseling and Homosexuality, Word Books, Waco, TX, 1988, p. 76.
[15] See The Mismeasure of Desire: The Science, Theory, and Ethics of Sexual Orientation (Ideologies of Desire by Edward Stein
[17] See en.wikipedia.org/wiki/Sexual_fluidity
Learn more:
- Issues Common Among Men Who Experience Same-Sex Attraction
- What is Same-Sex Attraction?
- How Do You Want to Respond to Your Same-Sex Attractions?
- How Can Family, Friends, and Church Leaders Help?