Made Gay?
What Makes People That Way?
What do we mean by “Homosexuality”?
This is a long banquet of a section. I’ve divided it into nine courses:
-
What do we mean by “homosexuality”?
-
Why what causes people to be gay matters for our debate
-
Does the Bible tell us anything about sexual orientation?
-
Is “gay” sex just a sinful habit?
-
Who takes part in “gay” sex?
-
What makes people gay? Social causes? The parental relationship theory
-
What makes people gay? Biological causes - general evidence.
-
What makes people gay? Biological causes – evidence of specific causes (warning - this is the scientific biggie!)
-
Conclusions
For those who don’t have the appetite for such a big meal you can just go straight to the taster menu – my Summary of the main points are linked here. You can always come back later and try one of the main courses!
1. What do we mean by “Homosexuality”?
Dictionary.com gives two main definitions of “homosexuality”:
​
-
“sexual desire or behaviour directed towards people of one’s own sex and gender”
-
“the state of being sexually attracted only to people of one’s own sex or gender.”
​
For millennia “homosexuality” by the first definition was well known, even though the word wasn’t. It usually involved married men who indulged in “sex on the side” with other males, like Roman slave-masters with their slave-boys. But homosexuality in its second meaning – only being sexually or romantically attracted to people of one’s own gender – wasn’t generally recognized until the late nineteenth century. In fact, the word “homosexuality” was only coined in 1868 and only became widely used from about 1901 onwards when German psychiatrists started studying this “new” issue.
It's on this second meaning of “homosexuality” (and “bisexuality”) I’m focusing here: those only sexually and romantically attracted to people of their own sex (or equally attracted to both). Before diving into the key Bible verses, it’s important we pause to look at the evidence of what homosexuality is (or isn’t). Does homosexuality in this second meaning even exist? Or is it just a false human construct to cover a particular type of sexual sin? And assuming this type of homosexuality is a real thing, what causes people to be that way? Are they born that way or are they only made that way because of what happens to them after they’re born? Or is it a mixture of the two?
The answer to these questions is important because it could well inform how we understand what the Bible verses were talking about at the time and how the Holy Spirit wants us to apply Scripture now. We need to understand what we are applying Scripture to before we apply it.
2. Why What Causes people to be Gay Matters for our Debate
What if there’s no such thing as fixed same-sex orientation?
If there’s no such thing as a fixed same-sex sexual orientation we’re ultimately free to choose which sex/gender we have sex with or marry. So, expecting everyone to conform with the “normal” traditional pattern of heterosexual sex and marriage should cause no harm.
What if it’s just caused by our social environment?
If same-sex orientation is simply caused by our post-birth social environmental, instead of embracing same-sex relationships, we should focus on healing the causes and effects of the damage to people's natural heterosexual nature. Otherwise, we’re promoting something harmful to people.
So, if same-sex orientation is just a product of imagination or society, i.e. man-made, Christians should oppose homosexual sex and marriage as harmful unless the Bible clearly and specifically encourages these things. I readily concede, it doesn’t! So, if after reading this section, you conclude same-sex orientation is just man-made, you can save yourself the bother of reading the rest!
But what if same-sex orientation is fixed by our biology?
But if same-sex orientation is fixed by biological factors - whether before or after birth - to force all gay people to only choose between heterosexual marriage or no sex and marriage, is likely to lead to harm for them and others, unless they're happy to be single and celibate.
We might still decide that the Bible’s message is so clear that, regardless of the nature of the relationship, all homosexual relations are wrong for all time. If so, to be faithful to Scripture, we should still oppose same-sex sexual relationships, regardless of the harm it may cause.
However, if we conclude the Bible teaches all same-sex sexual relationships are always wrong but also find condemning them causes harm rather than good, this should certainly give us pause for thought. Have we read the Bible’s message right? Because a harmful outcome of true teaching would be the direct opposite of what we’d expect. Because following God’s ways overall should do good rather than harm, and produce good not bad fruit (See e.g. Deut. 6:24 (RSV), 1 Cor. 10:24 and Matt.7:15-20).
If we conclude that the Bible’s only direct message is to condemn only certain types of same-sex activities in a certain place and time, then the harms or benefits of what we teach about same-sex relationships are likely to be key to discerning what aligns with God’s will today (see the verses just above). And if a homosexual orientation is fixed by our biology, this is likely to have a direct impact on the harms or benefits of accepting or opposing gay sex or marriage (I will fully explore this here in my final section, The Answers).
3. Does the Bible tell us anything about Sexual Orientation?
With one possible exception, I don’t believe the Bible says anything about sexual orientation; just like it doesn’t generally say anything about biology, physics, chemistry or astronomy. The Bible does not pretend to be an authority on the physical dimensions of people and things in this world. Its authority is about the spiritual and moral dimensions in our relationships with God, each other and our world. It tells us how that spiritual dimension works. But in terms of our physical world it’s a book of whys rather than hows.
The one place where I think Scripture possibly alludes to sexual orientation is Matthew 19: 11 (NKJV): “For there are eunuchs who were born thus from their mother’s womb, and there are eunuchs who were made eunuchs by men, and there are eunuchs who have made themselves eunuchs for the kingdom of heaven’s sake.”
The context of this verse was a debate about marriage and when and whether a man could divorce his wife. Jesus had just laid down a much stricter instruction about marriage and divorce than Moses: marriage between men and women should be for life and men should not divorce their wives. To this the disciples had reacted, “Wow! If that’s what marriage has to be like it would be better not to marry and stay single!” Jesus’s reply was - a single life isn’t for everyone, “but only [for] those to whom it has been given”, i.e. biological, physical or spiritual eunuchs.
In talking about "eunuchs" Jesus clearly wasn’t only talking about men without testicles, because he included himself - one who chose to live a celibate unmarried life for the sake of God’s kingdom (just as Paul would).
The second and third categories of eunuchs are pretty clear, but who did Jesus mean by “eunuchs who were born thus from their mother’s womb"? We can’t be sure. However, I would suggest that logically Jesus probably meant people who appeared male at birth, but were born without any sexual attraction towards women. Unlike most other men, such men would naturally not have sought to be married. Marriage between two men was then completely unheard of. And such “eunuchs” would have had no desire for the sexual relations with a woman expected in a marriage in order to procreate children. You would therefore expect many of these “eunuchs” to have chosen the then unusual path of singleness.
So, who could such men have been? From what science now tells us (see below) I believe this would probably have encompassed three categories men (of which the second two categories may slightly overlap):
-
Asexual males born without any sexual desire for either gender
-
Intersex people born with male genitalia, although sometimes incomplete, but who were genetically, chromosomally or hormonally more female than male and therefore sexually attracted to men rather than woman. (Today many of these individuals might identify as intersex, transgender female or non-binary)
-
Homosexual men who were only sexually attracted to other men and not women.
Today we also understand some people to be sexually and romantically gray, i.e. open to the possibility of a sexual/romantic union, but perfectly content to live a single, celibate life. I doubt Jesus was referring to such people because, given the then very strong cultural pressures to marry and procreate, such individuals would surely have followed the flow towards marriage.
Statistics from the latest UK census record significantly greater numbers of homosexual men than asexual or intersex “men”. There were censuses in Roman times (after all that was the backdrop for Jesus’s birth) but they certainly didn’t include questions about sexual identity! But there’s no reason to think that biologically first century Jews would have been very different to us. So, it seems very possible that Jesus was including homosexual men amongst the “eunuchs born [that way].”
If so, this would give scriptural support for a biological rather than social cause for people having an exclusively same-sex attraction, i.e. some people are just “born thus from their mother’s womb” rather than being “made that way by men”.
If Jesus was aware of men with an exclusively same sex attraction then there are two points to note here.
First, he was aware of something that very few, if anyone, of his day were aware of, including probably Paul and the other apostles (We’ll explore this later). But, as the Son of God, we might reasonably expect him to have greater insight than anyone else.
Second, he does not give such men licence to marry other men. Some might argue from this that Jesus therefore effectively ruled out same sex marriage for all time - the Master has spoken, so we don’t need to look any further. But, in my view, this argument doesn’t really hold water. The Master did not speak on that issue. It could just as easily be argued that if Jesus was aware of there being gay men but was opposed to them marrying each other why did he not rule that out? It would have saved these later church debates about the issue! In reality Jesus’s complete silence on the notion of same sex marriage is entirely neutral. The fact is there are all sorts of difficult ethical issues we grapple with today that didn’t trouble 1st century Jews. Jesus doesn’t address any of those issues either. As we’ll look at later, I believe there were very good reasons why (even if he would have supported it) it would not have been the right time for Jesus to proclaim the right of gay people to marry each other; any more than it was the right time to tell all slave owners to let their slaves free or for men to give women fully equal rights - and not just over divorce!
Jesus shared with us many deep eternal truths about his kingdom that apply equally now as then. But, as for how those truths apply to day to day practical ethical questions, he simply addresses the questions that were being asked at the time: Do we stone this adulteress? Do we pay taxes to Ceasar? Can we divorce our wives for any reason? He doesn’t directly address whether it’s OK to smoke pot, have IVF, use contraception, own a gun, drive a big fat diesel car, or for two men to get married. He doesn’t answer those questions because no one was asking them at the time.
4. Is "Gay" Sex just a
Sinful Habit?
What the Romans thought
In the first century Greco-Roman world there was no real concept that some men or women were born with an exclusively same-sex orientation. The almost universal view was that we were all capable of being sexually drawn to both sexes. By nature we could all be perfectly happy with sexual relations with the opposite sex, but some men chose to pursue sex with other men as an added extra to having sex with women. For many this was acceptable as long as the same-sex relationship respected certain societal codes: the higher status man taking the man’s naturally dominant role over the lower status man taking the woman’s role, most typically masters with their slave-boys. (In this patriarchal world women were just expected to keep their bodies for their husbands, although, as we’ll see, no one much cared what they got up to with other women!)
However, more conservative moralists of the time shared the views of writers like Plato who condemned all homosexual acts as against men’s natures and resulting from “an impulse in excess”. Typical of that view was the first century Roman philosopher, Musonius Rufus: “Not the least part of the life of luxury and self-indulgence lies also in sexual excess … For example, those who lead such a life crave a variety of loves, not only lawful ones but the unlawful ones as well, not women alone but also men; sometimes they pursue one love and sometimes another, and not being satisfied with those which are available, pursue those which are rare and inaccessible.”
My own personal experience
Sadly, I have my own personal experience of this. As a young boy for several months I was the victim of homosexual sexual abuse by a sexually mature male youth. (Thankfully quite mild – never going beyond touching). At the time it felt consensual, but I now realise it was anything but. Ever since then both myself and, I believe, the other person have only ever pursued relationships with females. I believe neither of us are homosexual nor even bisexual but fully heterosexual and yet at the time he (and even I) seemed to take some sort of pleasure in this same-sex erotic contact.
If we had continued these activities would they have become a habit which would have led us into a general homosexual lifestyle, so that we formed long-term sexual partnerships with other men? Effectively making ourselves “gay” by our own actions in our youth? At one time this caused me to wonder – was all homosexual “conduct” like that?
However, as I grew up, I realised that, despite that experience, I was only ever attracted to girls. From my nine year-old holiday crush with the feisty red-head Virginia to whom we confessed we loved each other “a bit”, to my first celebrity crush aged 11 to Debbie Harry, whose voice still tingles my skin, and my 12 year old’s first kiss and date with Sarah, lying about my age to get into the AA-rated film “Breaking Glass”.
And even today, despite being overwhelming in love with my gorgeous wife, I can confess to occasional crushes on other women I won’t name, as well as various celebrity crushes, including Julie Etchingham, Nicole Kidman, Alexandra Breckenbridge, Charlotte Ritchie, Dinah Asher-Smith and Brandi Carlile. It feels like a magnet drawing me towards them, which if it was allowed to, could (in my head) reach a physical culmination, but which I avoid thinking about save with my wife. Meanwhile, my list of man crushes has been forever empty.​
​
​​​By contrast, a bisexuaI acquaintance of mine, whilst also happily married to a woman, recalls that in his youth he had as many crushes on boys as girls.
And, even as my rather sheltered experience of life expanded, I came across occasional men and women who seemed “different” to me, who formed lifelong same-sex partnerships. I also couldn’t help but notice that most of them seemed to show traits of being a bit like the other sex, e.g. gay men with some slightly feminine qualities.
A young lesbian I met recently shared how growing up instead of playing with other girls she’d always preferred joining the boys in their games. So, as she got older she was happy enough to say yes when boys started asking her out. After all, she enjoyed being around boys, so why not let one of them be your “boyfriend” instead of “boy friend”? But it was only when she met her current partner, a woman, that she fell in love and realized here were feelings she’d never had for boys.
My own, limited, experience suggests to me there’s a distinction between different types of people who take part in same-sex activity :
​
-
those only interested in pursuing romantic relationships with the opposite sex (heterosexuals) but who sometimes indulge in sexual acts with people of the same sex (as my youthful teenage abuser had)
-
those romantically and sexually drawn to people of the same sex (homosexual or bisexual) regardless of who, if anyone, they have sex with.
​
These are effectively the two different dictionary definitions of “homosexuality” and “bisexuality”.
5. Who actually takes part in “Gay” Sex?
What the Statistics show
The statistical evidence overwhelming supports this dual meaning.
The numbers identifying as gay, bisexual or transgender
The 2021 Census for England and Wales included a voluntary question for over-16-year olds about their sexual orientation. Of the 44.9 million people who answered, the results were:
-
43.4 million (89.4%) identified as straight/heterosexual.
-
1.5 million (3.2%) identified with an LGB+ orientation - gay or lesbian, bisexual or other sexual orientation
-
Of the 3.2% identifying as LGB+, 1.54 % identified as gay or lesbian, 1.29% as bisexual/pansexual and 0.18% as “queer/other”
In addition, 0.5% of the overall population identified as “transgender”, i.e. with a gender identity different from their sex registered at birth.
​
See https://www.ons.gov.uk/peoplepopulationandcommunity/culturalidentity/sexuality/datasets/sexualorientation9categoriesbysexenglandandwalescensus2021
Intersex people - those born with biological characteristics of both sexes - weren’t identified by the Census. However, logically it’s likely a significant number of people who identify as transgender do so because they are in some way intersex (discussed further below).
The numbers taking part in same-sex sexual activities
Many are surprised to hear that only 3% identify as gay or bisexual. The sort of number they have in their heads is more like 10%. It’s almost certainly true that many older gay or bisexual people have not “outed” themselves and therefore would not have revealed this identity in a census. This seems to explain why the numbers identifying as LGB+ decreased steadily with age. So in the youngest age group (16-24 year olds), born into a world attaching little stigma to different sexualities, 6.9% identified as LGB+. But among the over-75s, who came of age in a world where men were imprisoned for homosexual acts, only 0.4% described themselves as LGB+. There might be an element of the youngest age group still “discovering themselves” increasing their LGB+ numbers. Perhaps the true number is closer to the figure for 25-34 years - about 5%? But that's still only half of that 10% many have in their heads.
This 10% figure came from the ground-breaking, but deeply flawed, research of Alfred Kinsey published in 1953. This was based on very skewed surveys in 1940s USA, including deliberate recruiting of subjects from prisons and the gay underworld. So, unsurprisingly, Kinsey ended up with disproportionately high numbers reporting same-sex sexual experiences. He therefore suggested that sexual identity for many people was changeable over their lifetimes. He concluded that about 13% of men and 7% of woman had predominantly homosexual experiences for at least three years of their lives - an average of 10% between the sexes.
Then, in 1973, Bruce Voeller founded the US National Gay Task Force, to campaign for better recognition of gays and lesbians. To support the organization’s campaign slogan, “We are everywhere”, he needed an equally memorable statistic. And he got it from the Kinsey report by which he could claim that 1 in 10 Americans were gay.
Conservatives, quite rightly, disputed this figure. They pointed to the 1991 US National Survey of Men, which estimated that only 2.3% of men identified as gay or bisexual. Yet by this time Bruce Voeller was able to proudly state that “the concept that 10% of the population is gay has become a generally accepted ‘fact’… As with so many pieces of knowledge (and myths), repeated telling made it so.” (Fake news started long before Donald Trump!)
In his 2015 book, Sex By Numbers, David Spiegelhalter drew on the widest survey of sexual behaviour since the Kinsey Report. He found that the proportion of people with same-sex sexual experience is far higher than the proportion who identify themselves as gay or bisexual. In fact, he noted the last big US survey had found that 10% of women and 3% of men who identified as heterosexual also reported full-on same-sex contact - an average of 6.5% heterosexuals having “homosexual” sex. So, most people who sometimes had same-sex sex were actually heterosexual!
​
This suggests that when it came to straight people having some same-sex “bit on the side” we’re not as different to our Greco-Roman ancestors as we thought. It seems these heterosexuals chose to have sex with people of the same sex, against their natural inclination, just to enjoy erotic variety with the same sex – just like those married Roman slave masters sleeping with their slave-boys - only now it’s more often women doing it.
This is entirely different to the small minority of people who identify as gay, lesbian or even bisexual. For them sex with someone of the same sex is the logical physical culmination of their natural romantic and sexual attraction. Gays and lesbians are physically wired for sex with the opposite sex, but it’s not what they’re internally wired for (see below for the likely reasons). It’s going against their own internal nature, which cannot be changed at will - no matter how many times a gay man sleeps with his wife. That's the conclusion of the overwhelming majority of reputable psychologists and psychiatrists globally.
​
The UK Royal College of Psychiatrists states that: "sexual orientation is determined by a combination of biological and postnatal environmental factors. There is no evidence to ... impute any kind of choice into the origins of sexual orientation ... homosexuality is not a psychiatric disorder. ... There is no sound scientific evidence that sexual orientation can be changed ... studies which have shown conversion therapies to be successful are seriously methodologically flawed. Furthermore, so-called treatments of homosexuality can create a setting in which prejudice and discrimination flourish, and there is evidence that they are potentially harmful." (RCP Position Statement on sexual orientation, April 2014)
​
​
6. What Makes people Gay?
Social Causes?
The Parental Relationship Theory
But if same-sex orientation is a genuine fixed condition is this just a product of our social environment? Are they “made [that way] by men”? Specifically, is this just down to your relationship with your parents? Until 10 years ago that’s what I believed.
I heard a Spring Harvest speaker 21 years ago explaining that no one was actually born gay. Science had failed to show there was any “gay gene”. It was something that happened to people in childhood. With gay men, like he’d “been”, it was nearly always caused by problems in their relationship with their father. I’d heard others say similar things before. I hadn’t been entirely convinced. However, this theory was now being shared by a Christian who himself “had been” gay. So, I lazily assumed it was true without looking further into it.
This theory is still widely held by conservative evangelicals today, and promoted by the popular pastor/speaker Mike Winger in his YouTube series, Speaking the Truth In Love.
Before looking into the scientific research, I started having serious doubts about this theory. My clear impression was that difficult childhoods/parental relationships are about as common or uncommon in gay people as straight people. This was even though you might expect some friction between fathers with more traditional views and their gay sons if they didn’t play the way boys were expected to.
Whatever you make of the revisionist works of James Brownson and Matthew Vines, one thing both authors can reliably attest to is their own experiences, as father and son: gay children coming from loving Christian homes where they have had good relationships with both parents.
So where did this supposed link between child-parent issues and homosexuality come from?
Sigmund Freud. In the nineteenth century, this Austrian neurologist became the father of psychology.
And we can certainly thank him for some things, including his ‘Talk Therapies’. These paved the way for modern-day therapies, enabling people with mental health issues to be treated in clinics instead of cruel “lunatic” asylums.
However, his actual theories were based on massively misunderstanding and overstating the influence of supposed childhood sexual urges. He quite literally had sex too much on the brain and read it far too much into others’ brains! He just over-sexualised everything (a mistake later repeated by some theologians, I believe). Modern psychologists overwhelmingly accept that on almost every point of his psychoanalytical theories Freud got it wrong, and badly wrong.
In his book, Freud: The Making of an Illusion, Frederick Crews says, “I’ve tried my best to examine his theories and to ask the question: What was the empirical evidence behind them? But when you ask these questions, then you eventually just lose hope.”
See https://www.amazon.com/Freud-Making-Illusion-Frederick-Crews/dp/1627797173
​
Yet Freud's theories of psychoanalysis caught on like wildfire and were widely adopted. Only after his death in 1939, did psychologists start questioning his ideas and increasingly recognized that his theories had little or no scientific basis. His development theory was dismissed because there was no proof that his Id, Ego, and Superego existed. His controversial Greek-inspired Oedipus Complex (a boy’s supposed sexual fixation with his mother) was found to be badly skewed and very inaccurate. His 5-stage child development theory really only took account of one factor- sexual urges, and ignored virtually everything else.
And it was also from Freud that we got the equally evidence-less theory that an individual’s sexual orientation resulted from issues with the parent-child relationship.
Alan Bell
Since Freud’s death rigorous scientific studies have found no reliable evidence that a same-sex orientation is ever caused by childhood relationships and experiences. One of the earliest major studies was published in 1981,Origins of Sexual Preference: Its Development in Men and Women, by Alan P. Bell and others. https://search.worldcat.org/en/title/7554715. They found:
​
-
no evidence that naturally heterosexual young people were recruited or seduced by "homosexuals" into a “homosexual lifestyle”. Instead, people’s natural inclinations usually determined their first sexual encounters. So, the large majority of LGB people experienced same-sex attraction about three years before their first sexual encounters.
-
there was only weak, non-significant evidence linking sexual orientation and child-parent issues.
-
all methodologically sound research found no difference in sexual orientation between children raised by straight and gay parents.
-
LGB individuals did experience childhood sexual abuse more often than heterosexuals. But where abuse happened it didn’t cause a homosexual orientation, rather their homosexual orientation caused the abuse due to negative reactions to early signs of their homosexual nature.
More recent research
In 2005, Dr Qazi Rahman, psychobiologist, and Glenn Wilson, a personality specialist, published Born Gay: The Psychobiology of Sexual Orientation, reviewing the previous 15 years’ research into why people are gay. They found that since groundbreaking work by neuroscientist, Simon LeVay, in 1990 there’d been an "absolute explosion" in such research.
They examined evidence from the fields of psychology, neuroscience, genetics, endocrinology and evolutionary biology. This found no evidence that people's sexuality is caused by their relationships in early life. Instead, the evidence indicated the large majority of us are born with our sexuality already defined. However, the causes are complex. There’s no one “gay gene” to explain it all but the research all pointed in one direction: biology – not the way people made us after we were born, but (primarily) the way they were “born thus from their mother’s womb…” They concluded that sexual orientation appears to be mainly determined by a combination of genetics and hormonal activity in the womb. Upbringing, childhood experience and personal choice have very little or no influence.
​
One thing was clear, said Dr Rahman: “… the classical gay man with a smothering mother and distant father idea … comes from Freud's oedipal complex theories. For most of us scientific psychologists, Freud's theory is like astrology to a physicist. In other words it's rubbish...Gay and straight men don't differ in their relationships with their parents. Where they do it might be put down to the fact that if you're a biologically gay boy, you are more likely to be feminine. You might well expect that fathers are not too happy. And mothers seek to protect." https://www.theguardian.com/education/2005/jun/16/highereducation.uk3?
​
The research also found no evidence that people could "learn" to be gay. Children of gay parents were no more likely to be gay than their peers.
​They concluded that between 2% and 4% of people are born gay because of these different biological factors, and this proportion does not seem to vary across societies. Men tended to be either heterosexual or homosexual, and male bisexuality was fairly uncommon. Women were more often bisexual than homosexual.
Further studies since then have only confirmed that gay parenting has no impact on sexual orientation. This included an extensive review of 72 social science research studies, Scientific Consensus on Whether LGBTQ Parents are More Likely (or Not) to Have LGBTQ Children by Schumm & Crawford . August 2019.
See https://vc.bridgew.edu/cgi/viewcontent.cgi?article=2154&context=jiws
Other social influences on our sexuality?
In 2010 Dr Rahman, with Swedish colleagues, published a huge study of 7,600 identical adult twins, Genetic and environmental effects on same-sex sexual behavior: a population study of twins in Sweden reported in Archives of Sexual Behavior. https://pubmed.ncbi.nlm.nih.gov/18536986/
They found that, amongst them, same-sex sexual behaviour was explained by both heritable genetic factors and unique environmental factors. But those environment factors were nearly always biological, especially for men. Their shared social environment, including family, rearing, shared peer groups, schools and communities had no effect on men, and just an occasional weak effect on women.
A further important paper was published in September 2016, Sexual Orientation, Controversy, and Science by JM Bailey and others. https://pubmed.ncbi.nlm.nih.gov/27113562/ They looked at studies of boys assigned as girls at birth due to damage to the penis, then reared and raised as females without telling them. Contrary to expectation, this did not make them feminine and they were all attracted to women not men.
7. What Makes People Gay? Biological Causes – General Evidence.
Gay Animals
For ethical reasons it’s often easier to research biological issues in animals than in humans. Some animals have long been known to indulge in homosexual behaviours. But is this just an occasional activity by routinely heterosexual animals? Or do some animals have a genuine homosexual orientation and is there a biological cause for it? Scientific studies have now found clear evidence for both.
Various studies of sheep have found that about 10% of rams will only mate with other rams, and about 20% will readily mate with both ewes and rams. See e.g. the research review in Gay, Straight and the Reason Why: The Science of Sexual Orientation (2017) by the leading neuroscientist, Simon LeVay.
Numerous studies have found neurological and hormonal explanations for why a minority of rams are male-oriented. For example, rams who preferred females typically had an ovine Sexually Dimorphic Nucleus (oSDN) about twice the size of male-oriented rams and ewes, and expressed higher levels of aromatase, which converts testosterone to estrogen.
Homosexuality has also often been observed in male and female penguins. This was highlighted in 2014 by the story of two “gay” Humbolt penguins at Wingham Wildlife Park Kent. Having bonded as a pair a few years earlier, they successfully hatched and reared an egg given to them as surrogate parents after the mother had abandoned it.
For further scientific evidence of homosexuality in animals see the various studies referenced in the Wikipedia page “Homosexual Behaviour in Animals” at https://en.wikipedia.org/wiki/Homosexual_behavior_in_animals
But what about us humans?
If there are biological causes for "gay" sheep and penguins, has science also found evidence for a biological cause for gay humans? Absolutely. So much evidence that, I've been forced to conclude that it’s now beyond reasonable doubt that people are nearly always made gay by their biology, and mostly occurring before birth.
It's true no one gene has been found in our DNA sequence to explain different sexual orientations. But those claiming this as a knockout punch to any biological cause are simply betraying they don’t really understand genetics or biology.
As Dr Rahman reported, over recent decades there’s been an “explosion” of knowledge and understanding of how our biology affects our gender and sexuality following a huge number of scientific studies. But it’s complex stuff, because God made us as complex stuff! After all, “We are fearfully and wonderfully made.” (Psalm 139: 14).
Unlike with sheep, there’s no one single biological or genetic process we can point to and say “Aha! That’s why we turn out gay, straight or bi.” Instead, research has found various factors affect our sexual make-up, many of them interacting and influencing each other and some playing a bigger or lesser role or no role at all in different individuals. There is still much to discover about the exact biological processes. However, as we'll see, the overwhelming majority of scientists specialising in this area have now reached the following consensus : our sexuality is almost always caused by a complex interplay of biological factors - neurological, genetic, epigenetic, hormonal, chromosomal, and biological environmental influences, mostly occurring before we're born.
For a summary of much of the scientific research on this issue discussed see A Short review of biological research on the development of sexual orientation, 2020, by Bogaert & Skorska and the sources cited there:
https://www.sciencedirect.com/science/article/pii/S0018506X19304660
There are two types of scientific evidence, which we’ll look at in turn: first, general evidence pointing very strongly to a biological cause without identifying the precise mechanism; second, evidence indicating specific biological processes that cause our different sexualities.
General Evidence of Biological Causes
Childhood behaviour
Numerous studies have consistently found childhood non-conforming behaviour to be a very strong predictor for gay or bisexual orientation. For boys this may include cross-dressing, playing with dolls, disliking competitive sports and rough play, and preferring girls as playmates. For girls this may include dressing like and playing with boys, and showing interest in competitive sports and rough play. Such behaviour typically emerges early on – often as young as two years’ old, and usually persists despite efforts to encourage them to behave like a “normal” boy or girl .
That 2016 study review by JM Bailey and others (Sexual Orientation, Controversy, and Science) estimated that 89% of gay men and 81% of lesbian women had an early history of gender nonconforming behaviour.
Studies of sexually re-assigned infant boys
The Bailey study review found that the above was strongly supported by medical experiments where, due to damage to their penis, infant boys were sex-reassigned and reared as girls. As noted earlier, this did not make them feminine or attracted to males. As the researchers concluded, “This is the result we would expect if male sexual orientation were entirely due to nature, and it is opposite of the result expected if it were due to nurture.”
Identical twin studies
Identical twin studies have shown that if one twin turns out gay the other is also likely to be gay, even if they’re separated at birth. Studies have found identical twins are more likely to have the same sexual orientation than non-identical twins. This indicates that genes have some influence on sexual orientation. However, even identical twins may have separate amniotic sacs and placentas, resulting in different hormone exposure. The big 2010 Swedish study referred to earlier found that same-sex behaviour in the identical twins studied was probably explained by both heritable genetic factors and unique biological environmental factors, including the womb’s environment, and exposure to early childhood illness. They found that influences of the shared social environment, had no effect for men and only a weak effect for women.​
Olfactory evidence!
Other Swedish research by Ivanka Savic in 2005 indicated gay and straight men generally respond differently to odors believed involved in sexual arousal. https://pubmed.ncbi.nlm.nih.gov/15883379/ When both heterosexual women and gay men were exposed to a testosterone derivative in men's sweat, a region in the hypothalamus was usually activated. Heterosexual men had a similar response to an estrogen-like compound in women's urine. The conclusion was that sexual attraction, whether same-sex or opposite-sex oriented, probably operates on a similar biological level.
8. What Makes People Gay? Biological causes –
Evidence of specific causes
Neurological causes
Unlike with sheep, differences in brain structure do not seem to be the main cause of our different sexualities, but they do appear to be a factor in many cases. There is some evidence of different sizes of certain parts of the brain between men and women generally. In some gay/bisexual individuals the sizes of these parts are more like the opposite sex. For example, research has found that straight men had right hemispheres 2% larger than the left, and in straight women, the two hemispheres were the same size. But in gay men, the two hemispheres were typically the same size, like straight women. In lesbians, the right hemispheres tended to be slightly larger than the left, similar to straight men’s.
Epigenetic causes
For humans it seems the biggest single biological factor determining our sexuality is genetic but it’s not in our DNA. It’s our epigenetics – genetics, but not as we may know it. These are factors outside our DNA sequence that don’t change our genetic sequence but do affect the way our genes “express themselves", i.e. talk and behave.
These epigenetic factors affect a lot more than our sexuality and, e.g, can cause certain diseases. These factors can turn on or off certain genes temporarily or permanently. These include factors which alter proteins around which our DNA can wrap itself. These include biological environmental factors, e.g. things happening in the mother’s womb as a fetus develops, early childhood illness/trauma, our diet and exposure to certain chemicals and drugs. There’s a good summary on the Wikipedia page on “Epigenetics” at https://en.wikipedia.org/wiki/Epigenetics - see especially the diagram on “Epigenetic Mechanisms” (If you want to delve further follow the external links to the source research).
Testosterone and INAH3
​
One major epigenetic factor which appears to determine our sexuality is how certain hormones in the mother’s womb interact with a developing fetus’s brain nuclei. This was first observed by Simon Levay in 1990 (see his book referenced earlier). This is discussed within Bogaert & Skorska's A Short review of biological research on the development of sexual orientation, 2020 (https://www.sciencedirect.com/science/article/pii/S0018506X19304660 ) The nucleus INAH3, located in the rear hypothalamus, is involved in directing typical male sex behaviour, such as attraction to females. It seems that if enough “male” hormone testosterone is received by INAH3 by 12 weeks after conception, the testosterone stimulates the enlargement of that nucleus INAH3. But if INAH3 doesn’t get enough testosterone by 12 weeks, the “female” hormone estrogen, also circulating in the womb, can stop INAH3 getting to the size/cell density typically seen in males. When that happens it seems INAH3 may function as female or partially female. This may cause male same-sex attraction. It seems the opposite can happen in certain females resulting in female same-sex attraction.
Supporting this finding are studies of the right hand finger digit ratio, a marker of prenatal testosterone exposure. Numerous studies have found lesbians on average have significantly more masculine digit ratios than other women.
The direct effects are hard to measure in humans for ethical reasons. However, animal experiments where scientists manipulated exposure to sex hormones during gestation generally induced lifelong male-typical sexual behavior in female animals, and female-typical behavior in males.
Maternal immune responses causing male homosexuality
Maternal immune responses during fetal development may account for up to about 1 in 5 of gay/bisexual men. Research since the 1990s indicates that the more sons a woman has, the higher the chance of later born sons being gay – likely due to certain hormones released as a maternal immune response to having another male.
There is also evidence from Turkey that a mother’s autoimmune thyroid dysfunction may cause same-sex attraction/gender dysphoria in a developing male fetus.
​
See e.g. "Sexual orientation, fraternal birth order and the maternal immune hypothesis: review", 2011 by Bogaert & Skorska (https://www.sciencedirect.com/science/article/abs/pii/S0091302211000227# ) and also their 2020 short review paper discussed above.
​
Genetic causes
Recent studies have found strong evidence of multiple genetic factors which appear to affect our sexuality.
In August 2019, a genome-wide study of 493,001 individuals concluded that hundreds of genetic variants underlie homosexual behavior in both sexes, with five particular variants being significantly associated. (See Large-scale GWAS reveals insights into the genetic architecture of same-sex sexual behavior by A. Ganna and others at https://pubmed.ncbi.nlm.nih.gov/31467194/)
In October 2021, a Chinese study of 1,478 homosexual and 3,313 heterosexual men reported that two particular genetic factors (FMR1NB and ZNF536) appeared to influence the development of same-sex sexual behaviour. (See S Hu and others Discovery of new genetic loci for male sexual orientation in Han population at https://pubmed.ncbi.nlm.nih.gov/?term=Huang+BC&cauthor_id=34719679 )
Chromosomal causes and cross-over with Intersex issues
For a small number of people the chromosomes which determine our sex likely also play a big part in our sexual orientation. Despite what President Trump may declare, biological sex is not always straightforward nor necessarily binary. Yes, in the large majority of cases people are simply male or female. But, occasionally, people can be a mix of the two. Just as with the climate crisis, scientific facts do not change according to Presidential order! As microbiologist Dr Rebecca Helm writes on X/Twitter, you may be genetically male or female, chromosomally male or female, hormonally male/female/ non-binary, with cells that may or may not hear the male/female/non-binary call, and all this leading to a body that can be male/non-binary/ female. This is partly because, although the starting point is an X and Y chromosome make you male and two X chromosomes make you female, “there is only one gene on the Y chromosome that really matters for sex. It’s called the SRY gene.” Sometimes during the embryo’s development “that SRY gene pops off the Y chromosome and over onto the X… A Y chromosome with no SRY gene means that physically you’re a female, chromosomally you’re a male (XY) and genetically you’re female (SRY).” And a similar thing can happen with two X chromosomes.
Also, some genetic females produce more male hormones than some males do. And likewise some males produce more female hormones than some genetic females . Furthermore, for hormones to be effective the body cells need to hear them and sometimes those cells’ receptors get switched off.
These chromosomal, genetic and hormonal variations are what causes a small but significant minority of people to be intersex - born with biological characteristics of both sexes. This issue was highlighted recently in the brilliant BAFTA-winning film Conclave. (Spolier alert here if you’ve not yet watched it!) The right “man” ultimately elected Pope - after the frontrunners are each exposed for their failings - turns out to be intersex. This person appeared to be a man but had a uterus and ovaries. This fact is only revealed to the previous dying Pope and the senior Cardinal overseeing the election of the new Pope. Both chose to keep this quiet because otherwise God’s chosen person for the job would be disqualified because his gender is not male but intersex and technically only a man can be Pope.
Although the character in Conclave was fictional, there are many people who have such mixed biology. It is occasional but not rare. Studies have shown up to an estimated 1.7% of people have some intersex trait (about 136 million people – nearly the population of Russia), of which up to about 0.5% have mixed sexual or reproductive organs – (about 40 million people – about the population of Poland). See the research review in American Journal of Human Biology 11 2 2000 How sexually dimorphic are we? Review and synthesis at https://pubmed.ncbi.nlm.nih.gov/11534012/ ​
Sometimes - like the new Pope in Conclave - such people can look like a man or a woman externally, but internally – chromosomally, genetically or hormonally – are more like the opposite sex. Occasionally, their sex may be externally much more mixed with hermaphrodite genitalia.
Note - transgender and intersex are not the same thing. Transgender individuals are those who identify with a different gender to the sex they were assigned at birth. It’s well beyond the scope of this website to delve deeply into the complex issues of transgender. All I would say is that, as we've just seen, over the past 30+ years science has taught us so much about the biological causes for our sexuality. This has made many of the judgments I and others had previously expressed about "homosexuality" look rather foolish. Who's to say what science may teach us over the next 30 years about the causes for people's different gender identities?
It is very likely that at least some who identify as transgender or non-binary do so because they are biologically intersex. Unless and until they have the necessary biological tests they won't know. A case in point is the former Playboy model, Caroline Cossey. She had been assigned male at birth due to her external genitalia, but internally she was more female than male due to having a rare XXXY combination of chromosomes. She was unaware that this chromosome mix accounted for her desire to be surgically re-assigned as a woman until she had tests just before her surgery. (See https://en.wikipedia.org/wiki/Caroline_Cossey )
I would suggest it’s also very possible that for a small minority of gay, lesbian or bisexual people, a contributor to their sexual orientation may be because they are slightly intersex in some way. For example, physically a person may appear fully female but chromosomally might be partly male causing them to be sexually attracted to other women rather than men. That could equally apply to some straight people. And unless we have the necessary biological testing we’ll never know!
Just as with straight people, I expect only a small proprtion of gay or bisexual people are intersex. However, scientific evidence now shows that nearly always what causes their same-sex attraction is that in some way they have a little more of the opposite sex thrown into their biological mix. In any event, science has already shown us that our sex and sexuality can be rather more mixed than the universally binary position people of my generation were brought up to believe.
​
Finally, several chromosome linkage studies have now identified patterns of prevalent homosexuality in certain families associated with linkage to the X chromosome. In such families gay men had about double the gay uncles on their mothers’ sides compared to their fathers’. (See e.g. https://www.science.org/content/article/study-gay-brothers-may-confirm-x-chromosome-link-homosexuality )
For sure, Genesis 1:27 tells us that in the beginning, “in the image of [himself] God created [human beings] …; male and female he created them.” Science cannot disprove the truths of “God-breathed” Scripture. But, just as with earlier discoveries, science should inform the way we interpret God’s word over sex/gender and sexuality. Where the science is clear, I believe, it should act as a corrective showing that previous literal interpretations were wrong and, rather than emulating the “flat-earthers”, we need to understand Scripture in a way that fits the facts . We should understand that Genesis 1:27 cannot possibly have meant that human beings are only ever binary male and female, let alone only naturally heterosexual, because intersex people with mixed biological sexes are now an established biological fact - just like the Earth revolving around the sun rather than the other way around - contrary to the original interpretation of e.g. Psalms 93 and Joshua 10:12-14.
The scientific evidence is also now clear that our sexuality is almost always determined by biological factors, and mostly occurring before we're born.
Genesis 1:27 might mean humans were initially made simply male and female, and presumably heterosexual too (Adam and Eve certainly seemed to be and needed to be!) However, in describing humans as being created as "male and female", was the writer not continuing the same literary device he used earlier in this passage when talking of God creating "light" and "dark" and "land" and "sea". The writer did not mean he didn't also create mixed shades of the different extremes; not just light and dark but dawn and dusk, not just land and sea but marsh and swamp land. The writer was here using the common literary device of merism - a way of saying "everything" by mentioning its different extremes. (See https://share.google/aHWkwCiusVV4mZQUT )
For example, talking of "young and old" (as in Joel 2:28) does not exclude the middle aged! but means "everyone of every age". And isn't this same literary device used when Genesis describes humans as created. "male and female" ?This surely isn't meant to exclude and deny the existence of people who are a biological mix of the two - seen most obviously in intersex people. Thus is supported by the fact that the pre Christian Jewish Talmud did acknowledge the fact of intersexual variations of biological gender. And these seems to be included in Jesus's reference to "eunuchs born that way" in Matthew 19.
Most importantly, Genesis 1:27 surely shows that God's own nature spans the full breadth of what it means to be both male and female? Therefore, human beings are equally made in God's image, whether they are male or female or a mix of the two. In any event, the evidence clearly shows that after Adam and Eve humans evolved, so that just as e.g. humans became racially mixed, for a few our sexes became mixed - some in just a minor way to alter their sexuality, but for a small minority mixing up their biology more generally so that they became intersex. And perhaps in Genesis1:27 God was simply making the point that all humans were created equally in his own image, and yes that included women, despite society then treating them as men’s inferiors?
Conclusions
I’m not a professor of biology or psychology. I’m just an ordinary evangelical Christian who happens to be a reasonably good litigation lawyer, used to weighing up expert and factual evidence. And all the evidence I’ve seen from the published research leads me to the following conclusion, not just on the balance of probabilities but beyond reasonable doubt: our sexual orientation - the sex of the people we’re sexually and romantically attracted to (if any) - is nearly always determined by complex biological factors beyond our control. They mostly occur before we’re born and, in any event, are impossible to change by will, however much we might want them to. It’s nearly always hard-wired, especially for men. Those of us who are homosexual or bisexual seem to have a little more of the opposite sex thrown into our biological mix. This seems to be why, for example, anyone who has spent time with gay men will usually notice certain slightly feminine traits about most of them, because they will have a variation to their biology that makes them very slightly more like a woman. The reverse is true of lesbian women.
I don’t know for sure if when Jesus talked about “eunuchs” he was including homosexual men. But I do know the evidence is now clear that when it comes to people’s sexuality they are usually “born thus from their mothers’ wombs.”
The consequences of being born gay for our debate
This scientific evidence should give some reassurance to Christians who worry that if we don’t “correct” the world’s “pro-homosexual" teaching we risk turning our heterosexual children gay or bisexual. We won’t because, whoever is right or wrong in this debate, what makes people that way is not their upbringing or teaching but almost always their unchangeable biology, and mostly before they're even born. Hence,
the evidence now conclusively shows, children brought up by two mums or two dads are no more likely to turn out gay than children brought up by a mum and dad.
And if the biology of LGBTQ+ individuals is slightly mixed up from the assumed norms why is that a bad thing? Aren't most of us biologically mixed up in different ways? It may have no impact on our sex or sexuality, but it may make us different to the supposed "normal" in other ways - affecting our mind, body or personality. I'm very heterosexual but I can certainly see other variations to the "normal" in myself! And don't these myriad differences mostly come about from the complex biological processes through which God “knit us together in [our] mother’s womb”? And don't they make each of us “fearfully and wonderfully” and uniquely different? We might bristle sometimes at the diversity, but, I wonder, does God actually love and celebrate it?
This is far from the end of the debate biblical debate …
Many will argue that most or all of the above may be true, but people are born with natural tendencies and desires to do all sorts of things that are sinful and ultimately harmful to themselves and others. This includes a propensity towards violence or greed, addictions to alcohol, drugs or gambling or sinful sexual behaviour like paedophilia, incest or bestiality.
Is a same sex orientation like the desire to carry on these other sinful/harmful activities and lifestyles? Even if people are born only attracted to others of the same sex, isn’t it still sinful for them to physically realise that by having sex with someone of the same sex? This is an important question and for many years my answer to that was yes. However, the evidence has now convinced me that the the correct answer is no. But this is where we need to carefully examine Scripture with the guidance of the Holy Spirit. That’s what I’ll be doing in the next sections.
… but it should be part of the beginning
I believe that, as in other areas of life, our understanding of what Scripture says should be informed by our understanding of the subject matter we’re applying Scripture to. We need to be sure that where Scripture is talking about apples we don’t automatically apply it to things that turn out to be oranges, or even cabbages!
In understanding Scripture we need to be mindful of what the Bible writers did and didn’t then know. So, as we’ve seen, because the Bible writers didn’t have the same scientific knowledge we do, we now understand that God must have been speaking figuratively and not literally when the Bible describes the sun as going around the Earth or (for most but not all evangelicals) when it describes the Earth being created in six days.
We now know some more scientific facts the Bible writers didn’t – that, some people just have a biologically fixed same-sex orientation. Knowing this, can we now see that in some of the Bible texts used to browbeat LGBTQ+ people about their faithful same-sex relationships that God wasn’t really talking about them at all? Was he actually talking about other kinds of people and behaviours?
So, let’s now look at what God has actually said in his word and how that may apply to us today, starting in reverse chronological order with the New Testament!
