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The Transgender Movement: Addendum to the Review

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The Transgender Movement: Addendum to the Review

James R. Aist

Preface

In a previous article on the transgender movement, a comprehensive and scholarly review article by the Family Research Council was presented (13). The purpose of the present article is to touch on several important aspects of the topic that were either not dealt with at all, or deeply enough in my opinion, in that review. (The numbers in parentheses are keyed to the numbered references listed at the end of the article.)

What is Gender Identity Disorder?

Gender Identity Disorder (GID) – often called “Gender Dysphoria” to de-emphasize the mental delusion involved – is a mental disorder characterized by the feeling and belief that you are not really the gender of the body you were born in, but that of the opposite gender. Thus, a person born a male feels and believes that he is really a female trapped in a male body and identifies his gender as female, and a person born a female feels and believes that she is really a male trapped in a female body and identifies her gender as male. Such a person is said to be transgender, because he/she perceives their real gender to be opposite (trans) their birth gender. Conversely, a cisgender person feels and believes their real gender to be the same (cis) as their birth gender. Transgender people experience intense anxiety, distress and inner conflict, because their perceived gender does not match their actual, birth gender. These feelings and beliefs are, themselves, very real to the person experiencing them, but they do not correspond to the actual, biological gender. Therefore, they represent a virtual, rather than an actual, reality. That is to say, persons with GID are delusional with respect to their gender. The best estimates of the prevalence of GID put it in the range of 0.33%-0.47%, or less than one-half of one percent, of the general population (16). Thus, GID is not “normal.”

A Family of Psychoses

As Barber (5) and McHugh (10) have pointed out, GID belongs to a family of mental disorders, or “psychoses”, which are characterized, in part, by a mental departure from reality, referred to by psychiatrists as “delusion” (7). Perhaps the best known mental disorder of this family is anorexia. Anorexic people are actually skinny, but they feel and believe that they are grossly overweight. Transable is another mental disorder belonging to this family of psychoses. Transable people feel and believe that they are disabled, yet they are, in reality, physically whole and healthy people. And that brings us to transgender people. As mentioned above, they feel and believe that they are not really the biological gender of the body they were born in, but that of the opposite gender. This delusion has been likened to that of the Emperor in Hans Christian Andersen’s tale, “The Emperor’s New Clothes” (10). In that tale, the Emperor, believing that he wore an outfit of exquisite beauty imperceptible to the common man, paraded naked through the streets of his town for all to see. The people knew very well that the Emperor was deluded, but they were afraid to say anything to him about his nakedness, for fear of retribution.

So, how do we treat those who suffer from such delusional, mental disorders? Do we offer liposuction to anorexic people in order to affirm their delusion that they are fat and to ease their anxiety? Of course not; we feed them and get them therapy. Do we offer amputation to the transabled, or offer to poke their eyes out, in an attempt to bring their bodies into alignment with their transable delusion? Of course not; we get them therapy. Do we offer hormones and genital surgery to the transgendered to affirm their transgender delusions and help them feel better about themselves? Sadly, all too often, the answer to this question is “Yes”, when it should be “No.” The way to really help them is not to affirm their transgender delusions and assist them in mutilating their bodies, merely to help them feel better about themselves. Rather, we should refuse to affirm their gender delusion, treat them with dignity and respect, and encourage them to seek psychiatric help (10).

Perhaps the main reason that this particular psychosis is being dealt with differently than the other two is that transgender activists often seem to care more about helping the transgender people believe a lie to make them feel better about themselves than they care about the truth and the long-term psychological health of the transgendered (14). Who is really showing genuine love for transgender people, the one who affirms their delusional perception of their gender and encourages them to masquerade as a member of the opposite gender, or the one who challenges their delusion with the truth and encourages them to get the therapy they need to face the reality of their biological gender and begin to live comfortably, happily and honestly with it, if it persists? We don’t really help them by enabling them to add a life-long masquerade as a person of the opposite gender to a lifetime of mental delusion. Honesty and truth matter; there has to be a better way.

Children with GID

GID can begin to manifest when a child is just a few years old. In children, GID is highly treatable by psychotherapy (13). Nevertheless, transgender activists often recommend that parents affirm the child’s gender delusion and prepare the child to spend an entire lifetime living with this mental disorder, with the goal of going through the gender reassignment process at an “appropriate”, later age. Such an approach seems to ignore the fact that GID in children is not only treatable by psychotherapy, but that it resolves itself, spontaneously, 75% or more of the time by adulthood (11, 14). I can’t help but wonder how many lives are being ruined by this unthinkable travesty perpetrated on children and their parents by well-meaning mental health professionals, all in the name of political correctness and a misguided sense of compassion. Sadly, about 75% of the children whose GID resolves spontaneously identify as gay, lesbian or bisexual in adulthood (13, 16).

Apparent Causes of GID

There are basically two schools of thought concerning the cause(s) of GID. The long-held and historical explanation is that this disorder is caused by unresolved psychological conflicts and issues and traumatic experiences which are treatable, to a greater or lesser extent, by psychotherapy (10). Valid goals of psychotherapy include improved mental health, living more comfortably with GID, and abandoning the trans-gender, psychological delusion in favor of the cis-gender, biological reality. The other, more recent, and widely assumed explanation is that the cause is, somehow, biological in nature, rather than psychological, and is, therefore, unchangeable. As with homosexuality, the biological hypothesis involves such things as brain differences, hormones and genetics. But, how strong are the postulated influences of biological factors, and could they even possibly be sufficient to cause GID?

To answer this question, one would prefer to look at the evidence from studies of GID in identical twins with data taken from large, identical twin registries, as has been done with homosexuality (1). But, apparently, no such studies exist yet. To date the most reliable results have come from a very limited number of clinical studies reported in the literature. These studies have produced very small sample sizes that limit their statistical power and are subject to large sampling errors that can strongly bias the results. Nonetheless, it is of some value to examine the results of such studies, if only for their heuristic value.

In a sample of identical twins pairs in which at least one twin has GID, the percentage of twin pairs with both twins having GID is referred to as the “concordance” and is generally accepted to be a measure of the genetic influence on the development of GID. Diamond (8) assembled the clinical results from a number of different clinical reports on GID in identical twins, and found a concordance value of 38.7%. This level of concordance suggests that there may be a weakly moderate, non-determinant (i.e., non-causal) genetic influence on the development of GID.

Results of twin studies of homosexuality have shown that when large, relatively unbiased, twin registries are used to obtain the data base, the apparent genetic influence on the development of homosexuality is found to be much less than previously thought (15). Therefore, I speculate that the same result will be found someday for transgenderism, when twin registries are used (i.e., the real level of genetic influence on the development of GID will likely be found to be weak, perhaps in the 15%-20% range).

There is reason to believe that identical twin studies actually tell us more than what the genetic influence per se is. Because identical twins share the same womb during pregnancy, these studies presumably reveal the combined influence of all possible prenatal, biological factors, not just the genetic factors. Therefore, these results (8) actually suggest that the influence of all biological factors combined is not sufficient to cause the development of GID. In other words, it appears that no one is born with GID. Rather, GID seems to result partially from pre-natal, biological influences and primarily from post-natal factors and influences, such as unresolved psychological conflicts and issues and traumatic experiences.

What is a Christian Response to GID?

What does the Bible say?

Let’s begin with Genesis 1:27 (with Mark 10:6) and Genesis 1:28. God makes mankind, including transgender persons, in His own image as male and female. Recall that God Himself created the first two human beings, Adam and Eve. Thus, as male and female, mankind can manifest the image of God by participating with God in the continuing creation of new, male and female, human beings. GID can prevent this manifestation of the image of God in us and keep us from being the complete man or woman God desires us to be. Therefore, GID is not natural.

Now, let’s move on to Deuteronomy 22:5, where God gives us instruction concerning a common manifestation of transgenderism; namely, “cross dressing”: “A woman must not wear man’s clothing, nor is a man to put on a woman’s clothing. For all that do so are abominations to the Lord your God.” (Note that this Old Testament instruction is a moral law, and, as such, is fully in force in today’s Christian church.) The Hebrew word translated “abomination” in the KJV and MEV translations is translated in many other modern English versions of the Bible as “detestable”, disgusting”, “abhorrent”, or “hateful” to God, leaving no room for doubt that God does not approve of transgender acts. But notice further that the verse says that “all that do so” are, themselves, abominations (hateful) to God. “But”, you may object, “doesn’t God love sinners?” Indeed He does, but, at the same time, He also hates those who are sinning (Psalms 5:5, Psalms 11:5, Proverbs 3:32, Proverbs 11:20). This may be a surprise to you, but remember the good news: God’s perfect love has made a way for His hatred of sinners to be cancelled, through repentance and faith in Jesus Christ. This good news is for all who sin against God in any way, including transgender people.

Finally, we come to 1 Corinthians 6:9-10, “Do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived. Neither the sexually immoral, nor idolaters, nor adulterers, nor male prostitutes, nor homosexuals, nor thieves, nor covetous, nor drunkards, nor revilers, nor extortionists will inherit the kingdom of God. Such were some of you. But you were washed, you were sanctified, and you were justified in the name of the Lord Jesus by the Spirit of our God.” Professor Robert Gagnon, one of our most prominent, contemporary, evangelical Bible scholars, had this to say about this passage, and I quote: “Paul includes “soft men” (malakoi) in the offender list in 1 Cor 6:9-10, which in context designates men who attempt to become women (through dress, mannerisms, makeup, and sometimes castration), often to attract male sex partners. The fact that Paul includes such persons among those who “shall not inherit the kingdom of God” suggests that acting on a desire to become the opposite sex can in fact affect one’s redemption” (9). Fortunately (for them and us), the same passage goes on to say that the power and authority (i.e., the “name”) of Jesus is able to both rid them of their sinful behavior and save their souls!

Let’s look into this aspect a bit further. I see a parallel here with the condition of homosexuality. God does not hate homosexuals because they develop same-sex attractions; they do not choose to have them. But He does hate them when they choose to act on those feelings by having homosexual sex (a sin). Likewise, God does not hate transgender persons because they develop GID; they did not choose to be gender confused. But, when they choose to act contrary to His design and purposes (sin, e.g., by cross dressing, undergoing so-called “gender re-asssignment”, etc.), that’s when He hates them. And, this is the same manner in which God deals with mankind concerning any other kind of sin, is it not? We sin and trigger God’s hatred, not by being tempted to sin, but by giving in to the temptation and choosing to commit sinful acts. With that perspective, it should be easier for us to refrain from condemning transgender persons; for we all have sinned and come short of the glory of God (Romans 3:23).

And, here is a further, often overlooked, ramification of Deuteronomy 22:5 and 1 Corinthians 1:6-9. If a male-to-female transgender person has sex with a man, he is committing a homosexual sin, because he is, in reality, still a man. Likewise, if a female-to-male transgender person has sex with a female, she is committing a homosexual sin, because she is, in reality, still a woman. Do not be deceived: God will not be mocked by anyone masquerading as a member of the opposite gender. After all, He is the one who created man with the XY sex chromosome configuration and woman with the XX sex chromosome configuration, and no amount or manner of pretending will ever change that.

That brings us to my final point in this section. Some transgender activists accuse God of making people gender confused. So, let me be very clear about this: God does not make anyone transgender! What kind of a “god” would create human beings that he purposely made to be an abomination to himself?! The God of the Bible is neither sadistic nor self-defeating. While it is true that God does not make mistakes, it is also true that God, for the time being at least, does allow mistakes to be made. For example, does He not allow us to sin? So then, how is it that transgenderism developed in a world created by a sovereign, morally perfect God? The answer is right before our eyes: like homosexuality (2), transgenderism came about as the result of original sin (16) and the resultant curse under which all of creation will continue to be compromised until the return of Jesus Christ to restore God’s creation to its original, perfect condition. Until then, let us not slander God by accusing Him of creating in us the sin nature that we struggle against, regardless of how that sin nature is manifested!

How should Christians respond?

In short, we should not condemn transgender persons themselves, and, at the same time, it seems to me, we should not affirm their gender delusion. In this regard, however, Yarhouse (16) recommended the following approach : “If Sara shares her name with me, as a clinician and Christian, I use it. I do not use this moment to shout “Integrity!” by using her male name or pronoun, which clearly goes against that person’s wishes. It is an act of respect, even if we disagree, to let the person determine what they want to be called. If we can’t grant them that, it’s going to be next to impossible to establish any sort of relationship with them.”  In any case, we must treat transgender persons with dignity and respect, be honest with them, have compassion for their suffering, and pray earnestly for them. We should not try to “fix” them (16). If the opportunity arises, we should encourage them to seek God’s help through prayer and/or psychotherapy in order to work through their underlying psychological issues and concerns. As with all ungodly conditions and behaviors that afflict fallen mankind, God can say the word, and healing will come. Of course, whether, or how, He chooses to heal is up to Him.

Perhaps you would like to read what several, prominent, evangelical Christian leaders have recently written about a Christian response to transgenderism. If so, I refer you to references (6, 9, 12, and 16) at the end of this article. These are all potentially helpful articles for anyone who sincerely wants to be Christ-like in their response to the transgender movement. I especially recommend that you read the article by Yarhouse (16) and then the article by Gagnon (9), which is a response to it. As Christians, we must be careful to reach out to transgender people on our own terms, not theirs, if we want to help them find redemption in Jesus Christ. And that should be our end game.

A good, Christian website with personal testimonies and lots more information on GID is “Help 4 Families” (18).

Unrestricted Public Facilities: A Freedom Way Too Far!

For purposes of clarity, let me first point out that I am using the term “public facilities” to refer to all shared restrooms, locker rooms, changing rooms, dressing rooms and shower rooms (Did I leave anything out?) in the public arena (i.e., outside of private residences).

The review article (13) touched on this issue briefly, pointing out that male-to-female transgendered “females” are perceived to be less of a threat to real females in public facilities than are gender-normal males pretending to be transgendered, and that may be true. The threat is not only regarding actual sexual assault, but also voyeurism, where a gender-normal male would behave as a “peeping Tom” (a person who gets pleasure, especially sexual pleasure, from secretly watching others), as it were, and thus invade the bodily privacy of unsuspecting females.

And here’s an eye opener for you. I have discovered a couple of little-known fact that should, perhaps, be of even greater concern than the “transgender pretender.” Let’s assume, for a moment, that transgender activists are correct in asserting that the male-to-female transgendered “females” using women’s public facilities are going to outnumber the transgender pretenders. Then, the greatest threat could come, hypothetically, from the male-to-female transgendered “females” themselves, based on sheer numbers. But, you may ask, “Why would the male-to-female transgendered “females” pose a threat to the real females in women’s public facilities?” Here’s why: scientific studies (3, 4) have found that 73%-81% of male-to-female transgendered “females” are still sexually attracted to females! Moreover, only 25%-30% of transgender people having undergone gender re-assignment have had any kind of gender-confirming surgery, meaning that more than two-thirds of male-to-female transgendered “females” using women’s public facilities will still have their God-given genitals intact(17). Think about that for a moment, and then let me ask you this: Do you want male-to-female transgendered “females” with fully functional male genitals getting “turned on” sexually by your wife or daughter while using women’s public facilities? I didn’t think so. Moreover, it’s not difficult to guess what else they might feel compelled to do once they are sexually “turned on.” This is why I believe that male-to-female transgendered “females”, rather than transgender pretenders, could prove to be the greatest threat to women using unrestricted public facilities.

At present, we have laws against “peeping Toms.” They are arrested, tried in a court of law, and, if found guilty, given an appropriate jail sentence. But if male-to-female transgendered “female” peeping Toms can legally be in women’s public facilities and are, somehow, “caught in the act” by the victim, they could get off scot free, because it would be virtually impossible to prove that they were actually peeping, and they would have a legal right to be in the facility. Thus, legally enforced, unrestricted access to public facilities, in effect, legalizes voyeurism. And that just isn’t right!

The absurdity of shared public facilities has to stop! Gender-normal persons outnumber gender-deluded persons by a ratio of about 250:1. It makes no sense to put the personal interests of such a tiny minority above the personal interests of such a vast majority. Gender-normal persons’ safety and feelings matter too! Accommodating the needs of transgender persons by providing gender-neutral facilities is going far enough. Surely they can deal with their feelings and distress privately for a few minutes while they “do their business”, without having to victimize the gender-normal public to accommodate their mental disorder in the process! Furthermore, a policy of shared public facilities opens the door to sexual perverts and sexual offenders, making it easier for them to gain access to their potential victims and, potentially, to get away with it. No one is even allowed to ask about their perceived gender status. To force the gender-normal majority to compromise their safety (real or imagined) and their very real right to bodily privacy in public facilities is clearly “a freedom way too far!”

Transgender activists accuse gender-normal activists of creating an anti-transgender hysteria based on fear mongering, rather than real-life events, concerning unrestricted public facilities. So that you will know the truth, I have assembled just a few of the many recent reports where real-life conflicts have been caused by unrestricted public facility policies. You can decide for yourself if you think this is just anti-transgender hysteria based on fear mongering:

  • Sexual assault victims speak out (click HERE)
  • Man lounging around naked in girl’s locker room at college (click HERE)
  • Man strips in front of girls in locker room at pool (click HERE)
  • Nine-year-old girl in boys bathroom at school (click HERE)
  • Store lets men use women’s dressing room (click HERE)
  • “Transgender” sexual predator in women’s shelter (click HERE)
  • Men in women’s restroom prompts ACLU leader to resign (click HERE).

References Cited:

1. Aist, J. 2014a. What Twin Studies Tell Us about Homosexuality: Nature vs. Nurture. (click HERE)

2. Aist, J. 2014b. God Does Not Make Anyone Homosexual! (click HERE)

3. Auer, M., et al., 2014. Transgender Transitioning and Change of Self-Reported Sexual Orientation. PloS One. (click HERE)

4. Author unspecified. 2016. Transgender sexuality, References 7 and 8. Wikipedia. (click HERE)

5. Barber, M. 2015. Transwhatever. RenewAmerica. (click HERE)

6. Brown, M. 2015. Can the Church Embrace the Transgender Community? Charisma News. (click HERE)

7. Definition of Psychosis, New York Times Health Guide. (Click HERE)

8. Diamond, M. 2013. Transsexuality Among Twins: Identity, Concordance, Transition, Rearing, and Orientation. International Journal of Trandgenderism 14:1, pages 24-38. (click HERE)

9. Gagnon, R. 2015. How Should Christians Respond to the Transgender Phenomenon? First Things. (click HERE)

10. McHugh, P. 2015. Transgenderism: A Pathogenic Meme. The Public Discourse. (click HERE)

11. McHugh, P. 2016. Transgender Surgery Isn’t the Solution. Wall Street Journal. (click HERE)

12. Moore, R. 2015. What Should the Church Say to Bruce Jenner? The Christian Post. (click HERE)

13. O’Leary, D. and P. Sprigg. 2015. Understanding and Responding to the Transgender Movement. Family Research Council. (click HERE)

14. Sprigg, P. 2016. Transgender Activists Put Ideology Above Safety. Family research Council. (click HERE)

15. Whitehead, N. and B. Whitehead. 2012. Chapter 10. Twin studies: The strongest evidence. (click HERE)

16. Yarhouse, M. 2015. Understanding the Transgender Phenomenon. Christianity Today. (click HERE)

17.  Bernstein, L. 2015. Here’s how sex reassignment surgery works. The Washington Post. (click HERE)

18. Help 4 families. (click HERE)

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New Theory: Homosexuality Is a Mistake of Nature

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New Theory: Homosexuality Is a Mistake of Nature

James R. Aist

Introduction

Homosexuality is believed to be caused by some combination of biological and environmental factors. Several biological theories have been offered, the most feasible being the genetic, the hormonal and the epigenetic theories. In 2012, a new theory was introduced that combines aspects of the genetic theory with the hormonal theory. This is the epigenetic theory. Epigenetics is a relatively new and vigorously investigated field of biological science that deals with the regulation of gene expression (production of proteins) in cells. The components of chromosomes that regulate genes are called “epi-marks.” These include such things as methylated DNA and variously modified histone proteins, but do not include changes in the DNA sequences themselves that code for specific proteins.

The Theory

Rice et al. (2012) published a review article presenting a speculative and hypothetical model (theory) to explain the development of homosexuality in both male and female homosexuals. Their goal was to develop a model that would explain why 1) molecular studies have failed to conclusively identify “gay genes” and 2) concordance for homosexuality between identical twins is low (click HERE). The theory draws on research supporting the hormonal theory as well as known properties and functions of epi-marks. The model would explain homosexuality on the basis of epi-mark-controlled prenatal testosterone (a sex hormone) levels, to the virtual exclusion of a role for either a strictly genetic influence or post-natal environmental influences.

Normally, epi-marks regulating sexual orientation are “erased” after they have produced the intended sexual development (i.e., heterosexual males and females). But, occasionally, a mistake is made, and the epi-mark is not erased but is, instead, passed on to the next generation. According to the model, when this mistake is made, epi-mark regulated testosterone overexposure in a female fetus would result in a masculinized female who will prefer females (a lesbian), whereas epi-mark regulated testosterone underexposure in a male fetus would result in a feminized male who will prefer males (a gay). The low concordance in twin studies would be explained not by a low-level genetic influence, as is usually assumed, but by the occasional passing of testosterone-enhancing epi-marks from father to daughter (creating a lesbian) and of testosterone-limiting epi-marks from mother to son (creating a gay man).

It is interesting to note that this model posits homosexuality as an aberrant accident of nature, in which normal prenatal development of a fetus produces the intended effect (heterosexuality), and abnormal prenatal development produces an unintended effect (homosexuality) by mistake. Abnormal prenatal development results when a mistake is made and an epi-mark in a parent is not erased, but is, instead, passed on to the offspring, where its effect (homosexuality) is seen in the subsequent generation. Thus, according to this theory, homosexuality is a mistake of nature, and it is not biologically normal, as gay activists want us to believe.

Although this model is highly speculative and presently has very little, if any, direct experimental support, it does have merit as a scientific hypothesis, because 1) it would explain both male and female homosexuality, 2) it could explain the low concordance for homosexuality found in twin studies, 3) it seems to provide a feasible explanation for the long-term survival of a reproductively deleterious trait in the human population, and 4) it is, at least to some extent, testable. Only further research will determine whether or not this theory will join the many previous theories purporting to represent an almost exclusive influence on the development of homosexuality, all of which have failed.

Caveat

Twin studies have shown that the combined influence of all possible, pre-natal, biological factors (e.g., genetics, epigenetics, hormones, etc.) on the development of homosexuality in adults is only weak to weakly moderate (click HERE). Thus, post-natal influences (e.g., cultural, social and experiential factors) are far more influential than is epigenetics in the development of homosexuality (click HERE).

Reference Cited:

Rice, G., et al. 2012. Homosexuality as a Consequence of Epigenetically Canalized Sexual Development. Quarterly Review of Biology 87:343-368.

(For more articles on HOMOSEXUALITY, click HERE)

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What Twin Studies Tell Us about Homosexuality: Nature vs. Nurture

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What Twin Studies Tell Us about Homosexuality: Nature vs. Nurture

James R. Aist

(Note: Numbers in parentheses refer to specific, numbered references listed at the end of the article.)

Introduction

I presented a much broader treatment of possible causes of homosexuality elsewhere (click HERE). Most of the more recent research on possible biological origins of homosexuality has focused on the degree to which genes, along with other prenatal factors such as hormones and epi-genetics, may influence the development of homosexuality. In this regard, the most conclusive and telling results have come from studies of “identical” twins (who both have virtually the exact same complement of genes). Although it is commonly assumed that identical-twin studies reveal the influence of genes per se on a trait or behavior, the results of such studies have the unique advantage of reflecting, in fact, the combined influence of all possible, pre-natal, biological factors (e.g., genetics, epi-genetics, hormones, etc.) on the development of homosexuality in adults (1). This is because identical twins not only share the same complement of genes, but they also share the same pre-natal environment (their mother’s womb), where biological factors are postulated to operate.

Twin Studies: Overview

The design of research studies using identical twins has improved greatly since the mid-1990s, with the advent of large, twin registries which can afford much larger data bases and less biased sampling procedures. The former approach of recruiting identical twins via advertisements in gay and lesbian publications is now known to have a very strong “volunteer effect” that produced the appearance of relatively large genetic effects (1). Nevertheless, even with the use of large twin registries, the number of identical twin pairs found with homosexuality is often very small in individual studies, resulting in a standard deviation that is greater than the calculated genetic effect, meaning that the results are not statistically different from zero. In other words, the genetic influence or contribution in several of these studies may actually be zero, making definitive conclusions impossible. Whitehead and Whitehead (1) have presented and discussed, in some detail, these and other problems inherent in twin studies of homosexuality and have presented reasons to expect that the genetic influence on, or contribution to, homosexuality will eventually be agreed to be in the 10%-15% range (i.e., weak). One reason for this (anticipated) lower actual genetic influence is that epi-genetic effects operating through identical twins sharing one placenta probably represent about 15% of the total influence that has been attributed to genetics in published twin studies (2). Another reason has to do with the apparently predominant influence of post-natal environmental factors on the development of homosexuality (10). Schumm (9) found that children with homosexual parents are 12-15 times more likely than children of heterosexual parents to be homosexual as adults. This is the strongest environmental influence ever reported for the development of homosexuality, and it involves very close family members, the parent-child relationship. In a family environment, identical twins share a common bond and common experiences more so than do other siblings, including non-identical twins; siblings can’t be any “closer” than that. The results of a study by King and McDonald (8) illustrate how such a close, family relationship could inflate the calculated genetic influence on homosexuality in identical twin studies. They studied 46 twin pairs having homosexuality present in one or both of the twins in each pair and found that 54% of the twin pairs had discussed their sexual orientation with each other, 89% had “shared knowledge” of each other’s sexual orientation, and 30% of these twin pairs had actually had sex with each other. Because identical twins identify so closely with each other, and post-natal experiences  – especially close family relationships – strongly affect the development of homosexuality, it seems plausible, if not likely, that a homosexual member of a twin pair would influence the other member of that pair to embrace and explore homosexuality also, thus inflating the apparent genetic influence reported in identical twin studies. That is to say, a significant portion of what may appear, in identical twin studies, to be a genetic influence on the development of homosexuality may turn out to be, instead, a post-natal, environmental influence involving shared knowledge of sexual orientation and shared sexual experiences within identical twin pairs.

Twin Concordance Studies

The “pair-wise concordance” answers the simple question, “Where one twin of an identical pair is homosexual, what percentage of co-twins is also homosexual”. The mathematical formula for pair-wise concordance of identical twins is C/C+D, where C is the number of concordant (similar) twin pairs and D is the number of discordant (dissimilar) twin pairs found in the study. For example, if C=1 and D=9, then the pair-wise concordance would be 1/1+9=1/10 or 10%. This result would indicate that for every twin pair with both members being homosexual, there are 9 twin pairs with only one homosexual member.

Using data provided in several reports of large, twin registry studies in different countries, I performed a meta-analysis and calculated the range of pair-wise concordance to be 9.9% to 31.6%, with the average being 13.0% for males, 13.3% for females, and 13.2% when the raw data for males and females were combined. These pair-wise concordance values indicate that for every twin pair with both members being homosexual, there are 7 twin pairs with only one homosexual member. Now, compare this result to the range of theoretically possible outcomes where no twin pairs would both be homosexual (= 0%) and where all twin pairs would both be homosexual (= 100%) and you can see, intuitively, that a pair-wise concordance of only 13.2% would indicate a real, but relatively minor, contribution of genetics to homosexuality. This minor role is similar to the estimated level of genetic contribution to virtually any kind of human behavior (3) and is known to be non-determinative and, in many cases, treatable by therapy and/or counseling. For instance, the best example to date of a genetically related behavior (mono-amine oxidase deficiency leading to aggressive behavior) has shown itself remarkably responsive to counseling (3). Therefore, on the basis of pair-wise concordance in identical twins, it seems appropriate to conclude that there is, at the most, only a minor genetic contribution to the development of homosexuality, and that this relatively minor influence can be overcome (i.e., nullified) through behavioral therapy (1), which we know to be a fact (4, 5).

The other measure of concordance in twin studies is “proband-wise” concordance. This estimate of concordance is necessary in order to use both identical and fraternal twins in a study to disentangle the relative contributions to homosexuality of genetic and non-genetic (environmental) factors. The formula used is 2C/2C+D, which, compared to the formula for pair-wise concordance, gives much more weight to the individual twins (probands). The effect is to greatly increase, relative to pair-wise concordance values, the apparent genetic contribution to homosexuality in identical twin studies. To illustrate this point, if we use the example given above where the pair-wise concordance calculates to be 1/10 = 10.0%, the proband-wise concordance calculates to be 2/11 = 18.2%. Although it is less intuitive, proband-wise concordance is generally believed to give a better overall estimate of “genetic influence” than does pair-wise concordance.

Classical Twin Studies

While pair-wise concordance gives an intuitive indication of the genetic influence on homosexuality as expressed in identical twins, it does not provide information on what factors may provide the remaining, non-genetic influence. To answer this question, researchers are using other measures, broader-ranging questionnaires and more sophisticated statistical procedures to evaluate such things as heritability, additive genetic effects and postnatal environmental influences. In order to be able to put the results of classical twin studies into perspective, it is important to keep in mind that, by convention in the twin study literature in general, a genetic contribution of around 25% is considered weak, of around 50% is considered moderate and of 75% or more is considered strong (6).

In a meta-analysis, Whitehead (6), using the results from seven of the recent twin registry studies that were designed to reveal contributions of both genetic and non-genetic factors to homosexuality, found that the mean contribution of genetics to male homosexuality was around 22%, and to female homosexuality, around 33%. Because of the relatively large standard deviations in the data, these two values were not statistically different from each other.  Thus, the mean genetic contribution to male homosexuality in these studies is weak and to female homosexuality is weakly moderate. Such levels of genetic contribution indicate a real but weak-to-weakly moderate and indeterminate role of genetics in the development of homosexuality. For comparison, other traits that have around 50% (moderate and indeterminate) genetic contribution in twin studies include such things as divorce and alcoholism, while puberty has a 90% (strong and determinate) genetic contribution (1). Furthermore, the non-shared, post-natal environmental contribution to homosexuality is moderate to strong, around 64%-78%, has a relatively small standard deviation and is consistently around the same percentage (6), indicating that homosexuality is influenced primarily by post-natal environmental factors and experiences that are not directly related to prenatal, biological contributions of any kind or combination.

The recent study by Zietsch, et al. (7) can be used to illustrate representative research results obtained with large samples from twin registries. They used a very large sample (9,884) of twins from the Australian Twin Registry, one of the largest samples to date for twin studies of homosexuality. In this sample, there were 1,840 identical twin pairs (1,133 female and 707 male). Their calculated value of only 24% for the proband-wise concordance for homosexuality indicates a weak genetic influence. Moreover, their calculated figure of 31% for heritability of homosexuality also indicates a weak genetic component. This leaves around 68% of the variance represented by post-natal, “shared environment” and “residual” environmental influences combined.

Summary

In view of the fact that twin studies have shown that the combined influence of all possible, pre-natal, biological factors (e.g., genetics, epi-genetics, hormones, etc.) on the development of homosexuality in adults is only weak-to-moderate, it is important to understand that all of the biological theories combined can address only this weak-to- weakly moderate amount of influence, while ignoring the far more important post-natal influences (e.g., culture, parental divorce, and having a homosexual parent). Furthermore, twin studies clearly support the inference, based on results obtained through therapy and counseling (4, 5), that post-natal, environmental influences have a far greater role in the development of homosexuality than do pre-natal, biological influences. Thus, where the development of homosexuality is concerned, twin studies have demonstrated that nurture is far more important than nature.

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References Cited:

1. Whitehead, N. and B. Whitehead. 2016. Chapter 10. Twin studies: The strongest evidence.(click HERE)

2. Whitehead, N. and B. Whitehead. 2016. Chapter 1. Can genes create sexual preferences? (click HERE)

3. Whitehead, N. and B. Whitehead. 2016. Summary. (click HERE)

4. Whitehead, N. and B. Whitehead. 2016. Chapter 12. Can sexual orientation change? (click HERE)

5. Aist, J. 2012. Homosexuality: Good News! (click HERE)

6. Whitehead, N.E. 2011. Neither Genes nor Choice: Same-sex Attraction is Mostly a Unique Reaction to Environmental Factors. Journal of Human Sexuality 3:81-114. (click HERE)

7. Zietsch, B., et al. 2012. Do Shared Etiological Factors Contribute to the Relationship between Sexual Orientation and Depression? Psychological Medicine 42:521-532.

8. King, M., and E. McDonald. 1992. Homosexuals who are Twins. British Journal of Psychiatry 160: 407-409.

9. Schumm, W. 2010. Children of Homosexuals More Apt to be homosexuals? A Reply to Morrison and to Cameron Based on an Examination of Multiple Sources of Data. Journal of Biosocial Science 42:721-742.

10. Aist, J. 2012. Are Homosexual People Really Born Gay? (click HERE)