So a new study claims to possibly explain why homosexuality occurs. Naturally the news is getting around, and lots of ink will be spilled before this is all over.
- "Scientists May Have Finally Unlocked Puzzle of Why People Are Gay: Lesbians get it from fathers, gay men from mothers?" (US News and World Report)
- "Scientists claim that homosexuality is not genetic — but it arises in the womb" (io9)
- "Homosexuality’s Cause Isn’t Genetics, but the Answer Does Lie in the Womb: As long as natural selection has been an accepted scientific theory, homosexuality has been a riddle for scientists." (Medical Daily)
- "Group of Scientists Believe They Have Unlocked Hereditary Question of Why People are Gay" (Towleroad: A site with homosexual tendencies)
- "Your Womb Could Make Your Kid Gay. Seriously" (CafeMom)
- "Gene Regulation May Explain How Homosexuality Flourishes" (LiveScience.com, which has one of the clearer explanations of the concept, socially liberal biases aside)
With or without data, people will make the predictable overinterpretations, of course. Judging by the URL, io9's original headline apparently said, "Scientists confirm that homosexuality is not genetic — but it arises in the womb." Well, "confirm" has now been backtracked to "claim"; the study could confirm nothing of the kind because it's just not that kind of study. Rather it will present a model, a mathematical system that depends on plenty of assumptions and that might explain what's been observed. Says evolutionary biologist William Rice, the lead author, to US News,
We've found a story that looks really good[.] There's more verification needed, but we point out how we can easily do epigenetic profiles genome-wide. We predict where the epi-marks occur, we just need other studies to look at it empirically. This can be tested and proven within six months. It's easy to test. If it's a bad idea, we can throw it away in short order.
What is this idea? For starters, you need to know that along with genes themselves, which transmit any information that is properly called "genetic," there are "epigenetic" markers that influence how those genes are expressed. Some years ago when I taught a course that touched on debates about genetic determinism, I was quite taken with E. O. Wilson's example:
The same gene can produce different body types depending on environmental conditions. The classic case is the arrowleaf plant. If grown on dry ground, it produces an elephant-ear leaf; if grown in a pond, it puts up leaves like lily pads; and if grown in deeper water, it grows up with slender leaves like eelgrass.
So genes don't tell the whole story. Even identical twins could experience different environments, one of which triggered a particular gene to be expressed and one of which didn't--though to acknowledge that is a far cry from denying that genes are relevant at all, as some social conservatives are tempted to do as soon as the object of potential genetic influence happens to be homosexuality. Take, for example, this choice reaction to the new study from a reader at US News:
These Godless ignorant "scientists-so-called" (I Timothy 6:20) start off with a LIE: "The hereditary link of homosexuality has long been established" - BullS___! It's been "medically & scientifically" PROVEN to be a lifestyle CHOICE, partially based on being over-mothered for boys, & over-"fathered" for girls, but mainly it's just plain SIN against our Holy Creator-God, just like all the other sins we all have committed, and until we "confess our sins", "repent"(turn away from them), and give our whole hearts & lives to God through Jesus Christ, the only One Who suffered and died on that cross to take our sins on Himself and pay for our Salvation and forgiveness, we will continue to live in whatever life of whatever sins we choose to live in. These are the end times...no one knows the day or hour, but we can and are commanded to "know/discern the times". He's coming again soon. Please, turn to Him, trust in & live for Jesus, before it's too late.
(Okay, dude, I get it that you're angry, and that you want people to recognize the truth about repentance and salvation, but honestly, if you think using a tone like that is likely to get you anywhere with the people you're trying to convert, you're ... ahem, sorely lacking in the virtue of prudence. There are better ways to critique the "born gay" routine.)
Anyway. The puzzle in evolutionary theory with regard to homosexuality is how a tendency towards nonreproductive sexual behaviour could survive in a population. To put it in the starkest terms, if nobody who has a "gay gene" ever had penile-vaginal intercourse, then the gene would die out in a generation because there would be no offspring carrying the gene. In the real world, of course, people carry genes for traits they don't themselves exhibit and sexual behaviour is a good deal more complicated in any case, but on the face of it there would still seem to be an evolutionary disadvantage to any gene that influenced someone towards not reproducing. Various attempts to account for the persistence of homosexuality have suggested, for example, that gay uncles are somehow good for their nieces and nephews, who carry genetic material similar to their own, in a way that yields a net reproductive benefit to the family. Which is pretty much speculative and hardly more convincing than most evolutionary psychology.
The new study might change that, in that it suggests an actual mechanism of action by which a tendency towards homosexuality might be inherited without getting selected out.
Epi-marks constitute an extra layer of information attached to our genes' backbones that regulates their expression. While genes hold the instructions, epi-marks direct how those instructions are carried out – when, where and how much a gene is expressed during development. Epi-marks are usually produced anew each generation, but recent evidence demonstrates that they sometimes carryover between generations and thus can contribute to similarity among relatives, resembling the effect of shared genes.
Sex-specific epi-marks produced in early fetal development protect each sex from the substantial natural variation in testosterone that occurs during later fetal development. Sex-specific epi-marks stop girl fetuses from being masculinized when they experience atypically high testosterone, and vice versa for boy fetuses. Different epi-marks protect different sex-specific traits from being masculinized or feminized – some affect the genitals, others sexual identity, and yet others affect sexual partner preference. However, when these epi-marks are transmitted across generations from fathers to daughters or mothers to sons, they may cause reversed effects, such as the feminization of some traits in sons, such as sexual preference, and similarly a partial masculinization of daughters.
The study solves the evolutionary riddle of homosexuality, finding that "sexually antagonistic" epi-marks, which normally protect parents from natural variation in sex hormone levels during fetal development, sometimes carryover across generations and cause homosexuality in opposite-sex offspring. The mathematical modeling demonstrates that genes coding for these epi-marks can easily spread in the population because they always increase the fitness of the parent but only rarely escape erasure and reduce fitness in offspring. (Source)
Now first, before anyone flips out, don't read too much into the terms "masculinization" or "feminization," either on my part (Not My Study!) or the researchers'. A Towleroad comboxer who appears to have biological training cautions others:
"Masculinization" and "feminization" does not mean you play more sports or speak with a lisp; it is referring to the biological process by which the sexes are differentiated and developed during maturation. These two terms are simply the shorthand titles for these processes.
Anyway, the researchers' conjecture is interesting. Has it been empirically confirmed? Hardly. Can we expect blazing headlines within the next year if the conjecture is disconfirmed? I doubt it.
Now, should the authors have waited for empirical support before publishing? I don't actually think so, even if they may be wrong. I'm no geneticist, but some ideas are what you might call "interestingly wrong"; regardless of their own merits, they'll stimulate new lines of investigation, as a result of which we'll ultimately understand the natural world a little better.
Whether any of this research will be of practical benefit to people, now that's a different matter. It's what people make of it from a social and moral angle that I find most interesting.
And the moral implications would be pretty negligible in themselves, so far as I can see. As a Catholic I uphold a fundamental distinction between person, inclination, and act.
- A person with homosexual inclinations (including yours truly, let me point out for the benefit of readers who are new here) has intrinsic dignity, being made in the image and likeness of God.
- A homosexual inclination is "objectively disordered," (CCC 2358) that is, disordered in the object towards which it tends. But it's not considered sinful to experience the desire.
- "Homosexual acts are intrinsically disordered. ... Under no circumstances can they be approved" (CCC 2357).
Whether or not anyone likes this approach and the philosophical distinction that underlies it, it's stable in the face of new empirical claims (which the new paper does not supply in any event). With or without an acknowledgment of some genetic influence on homosexual desires, the intrinsic dignity of the person with those desires would remain unaltered, as would the moral logic against homosexual acts.
Look, to use an imperfect analogy (and yeah, some people will hate it, I know, 'cause I used to hate it myself), we know that a tendency towards alcoholism is sometimes inherited. With or without that tendency, the person who drinks to excess is still valuable. At the same time, any genetic tendency doesn't alter the disordered nature of the act of drinking to the point of intoxication, though it may mean a particular person is less culpable for it.
Crudely put: We're not responsible for our desires; we're responsible for how we act on our desires. This study doesn't change that.
Now I can sympathize with a certain skittishness over at Towleroad, where comboxer Joshyboy wonders if all this research will be misused.
Although it's an exciting prospect to think that there could be scientific data that will make a strong case to show that being gay is a natural occurance. I am secretly praying that there isn't a gay "gene".
Just think, if it turns out to be the case - super conservatives will label being gay as a "genetic disorder"! They will find ways of isolating this "gene" and eliminating it in young children or even unborn babys, effectively "curing" the child of potential homosexuality...my thinking is that it all leads to a very scary place.
I can't speak for all conservatives, but I can assure Joshyboy that orthodox Catholics will defend the rights of anyone with the "wrong" genetic or epigenetic material.
The study will be published soon enough. When it does come out, I hope people will take the long view.