Nothing Up My Sleeve; or, The Silence of the Genes

At first I thought I'd just add to yesterday's post, but decided to start a new one.  After I clicked on Publish and moved on to other matters for the evening, I kept wondering what valid a use a "genetic" test to detect homosexuality could have.  After all, LGBTQ folklore has it that we know from an early age that we're Different, so who needs a test?  I can imagine a confused and frightened young person wanting to take such a test to prove to himself or herself that she isn't gay, and then having to face positive results.  Maybe parents would drag offspring they aren't sure about to the doctor to settle the question one way or the other.  By analogy to similar tests, the only use I can think of for this one would be "diagnostic," and what valid diagnostic use would a test for homosexuality have?

One of the New Scientist articles I linked to yesterday acknowledged some of these concerns.

This concern may be premature. Marc Breedlove at Michigan State University in East Lansing points out that in its current form, the test is not accurate enough to be used to predict whether someone in a new population of individuals is gay with any certainty, since the 67 per cent accuracy of the test is only relevant for the test population, who are themselves not reflective of the general population, in which a much lower proportion of people are gay.

Nevertheless, some researchers contacted by New Scientist raised concerns over the ethical implications of such research. For example, if the test were developed further, could it one day be used to screen for sexuality at an early age?

“Eugenics is always a possibility, but governments that regressive would rarely have enough money to spend on something like this,” says Alice Dreger an ethicist and historian of sexuality. “More likely it would be used by parents.”

Dreger recalls an anecdote from a researcher who studies the fraternal birth order effect. The researcher received a phone call from a man in the US who was looking to hire a surrogate mother – but because of the effect did not want someone who had already had several sons. “That’s not really what I want…” the man had said, “especially if I’m paying for it.”

I wonder about Dreger's remarks.  Once science and commerce have done that voodoo that they do so well, the hypothetical test would soon be affordable, not just for parents (!) but for "governments that regressive."  Regressive governments (like the poverty-stricken Saudi Arabian regime, maybe?) don't have to develop the science themselves, they just need to find a way to pay for it from the aid they receive from the United States.  Even a "centrist" administration will probably go along with selling the test abroad -- finding overseas markets for American products is a bipartisan priority.  Regressive and repressive governments also aren't much concerned with accuracy; a few false positives leading to the execution of non-gay individuals would hardly bother them much.  Where do they find these people?

And yes, of course there are parents who'd be interested in such a test.  Since most antigay bigots reject biological-determinist explanations of homosexuality, one could mock them for using a test based on a biological-determinist explanation of homosexuality.  Bigots are quite comfortable with biological-determinist theories that support their bigotry, and besides, better to be safe than sorry.  In the hypothetical case I outlined above, of parents taking their child to the doctor to be tested for homosexuality, they could still follow up by trying to beat the Gay out of him or her.  I haven't noticed that inconsistency bothers many people.

Dean Hamer, in his New Scientist piece, claimed that "such work won’t worsen homophobia. People who understand the role of biology in sexuality are more likely to be accepting and inclusive." It's a bit odd, really, to find a scientist reassuring the public that there's nothing to worry about because the science doesn't work yet.  The usual line in scientific evangelism is that you can't stop the forward march of Knowledge, and if we can't detect gays with a saliva test today, we'll be able to do so Real Soon Now.

Even forgetting people like Günter Dörner, the German endocrinologist who "classified homosexuality as a 'central nervous pseudohermaphroditism'" resulting from low levels of male hormone in homosexual males, it isn't only "people who understand the role of biology in sexuality" that we have to worry about -- it's the people who don't understand the role of biology in sexuality.  But that group includes a lot of scientists working in the field.

For example, the NBC story that Queerty used as a source for their post included this significant passage:

Dr. Margaret McCarthy, who studies the developing brain at the University of Maryland School of Medicine, said epigenetic changes could happen while a fetus is developing. 

"Developing male fetuses produce very high quantities of testosterone during the second trimester and this directs psychosexual development along masculine lines, a component of which is preference for females as sexual partners," McCarthy said in a statement.

"This study provides a major step forward in our understanding of how the brain can be affected by factors outside of the genome. It is also possible that the experience of being a homosexual or a heterosexual has itself impacted the epigenetic profile. But regardless of when, or even how, these epigenetic changes occur, their findings demonstrate a biological basis to partner preference."

It appears that Dr. McCarthy accepts the popular scientific notion that male homosexuals are in some way feminized, since we have a preference for males as sexual partners, instead of females as "masculine" psychosexual development would produce.  But she's wrong about the effects of hormones, which produce not partner preferences but, at most, roles in sexual behavior: lordotic males who present themselves to be mounted by partners of either sex (or a researcher's finger stroking their backs), female who mount partners of either sex.  They don't explain why a 'normal' male would mount a lordotic male, or a 'normal' female present to a masculinized female.  (This behavior has nothing to do with human homosexuality, but pointing that out would undermine their claims to explain human homosexuality.)  I can't see where McCarthy got the idea that Ngun's "findings demonstrate a biological basis to partner preference," because they demonstrate nothing of the kind.  It's certain that biology provides a "basis" for sexual behavior, as it provides a basis for language and other cultural phenomena; without bodies (biology) these phenomena wouldn't occur.  But the variations in language, culture, and sexuality have not been shown to be determined by biological differences.  But environment and culture also provide a basis for sexual behavior.  The bogus nature/nurture divide is still active in the scientific community.

Many scientists are naive, to put it nicely, about the motives of the people to whom they hand over the new toys they've invented.  Even a low-tech intervention like abortion can be used to bigoted ends, as when it's used to prevent the birth of daughters -- especially when it's combined with higher technology that allows the sex of the embryo to be known during gestation.  It might be acceptable to push for a saliva test that detects homosexuality if it had some positive use, but no one seems to have any idea what that would be, and there are plenty of negative consequences that are all too plausible and likely.

Hamer also brushed aside concerns about a test: "... Ngun’s work does not amount to a sexual orientation test. Even if it can be replicated in more twins with highly correlated methylation patterns, it is unlikely to work in unrelated members of the public."  Why is Hamer so negative?  Doesn't he have faith in scientific progress?  Just because we can't do something now doesn't mean we won't be able to do it later!

So what is the value of Ngun's work, even dismissing all the criticisms of its weaknesses (weaknesses that also characterized the research that made Hamer famous, as it happens)?  Hamer wrote, "My fear is that the furore stirred up will inhibit it. That would be a pity, because sexual orientation is one of the most fundamental and fascinating variations in humanity that we can study."  I disagree with him on both those counts.  I don't think that sexual orientation is particularly fascinating or fundamental, any more than differences in skin color are.  If, as various streams of the LBGT movement have argued, homosexuality is just not a big deal, not a difference that matters to individuals' value or capacity as human beings, then how is it "fundamental"?  One of the points of the Kinsey scale is that homosexuals and homosexuals can be thought of as different in degree, rather than in kind.  Is a Kinsey 2 fundamentally different from a Kinsey 3 or 4?  Where do you draw the line?  For that matter, why is a difference in sexual orientation more fundamental or fascinating than the fact that people are not equally attracted (or attracted at all) to all people of a given sex?  I'm not attracted to all men, and I'm often not attracted to men whom other men desire fiercely.  That looks to me like a more fundamental difference than sexual orientation, but scientists like Hamer don't seem to find it fascinating.  (It's a difference that they either try to overlook, or try to explain by claiming that some people are inherently more attractive, on evolutionary grounds.)

Is a difference in sexual orientation more "fundamental," say, than a difference in language or religion?  Such differences have been taken to be important, to be markers of fundamental human difference worth fighting and killing over, but they are not.  I think it needs to be argued, not postulated, that sexual orientation is fundamental.  Hamer assumes that differences in "sexual orientation" are both fundamental to the individual, and must (therefore?) be based in the genes in some carefully nonspecific way.  Even if he were right about this, decisions of funding need more than his dogmatic assurances, which seem to be motivated by PR aims to justify supporting the work.

Another notorious researcher takes the same tack:

“The scientific benefit to understanding [why people vary in sexual orientation] is obvious to anyone with an iota of curiosity,” says Michael Bailey at Northwestern University in Evanston, Illinois. “The predictive test needs replication on larger samples in order to know how good it is, but in theory it’s quite interesting.”

What I find interesting is that Bailey reads Ngun's study in a way diametrically opposed to Hamer: Hamer dismisses the possibility of a "predictive test," while Bailey sees it as feasible as well as "quite interesting" in theory.  He doesn't seem to have a valid use for it, though. And neither Bailey nor Hamer seems to have noticed the serious flaws in Ngun's study listed by Ed Yong at The Atlantic, which indicates a lack of important analytic skills on both their parts.  Other than that, Bailey can only handwave that it's obvious that understanding variation in sexual orientation has a scientific benefit.  Maybe it has a benefit, maybe not, but that's not obvious.  As Noam Chomsky wrote decades ago about American race-science bearing on intelligence:

A possible correlation between mean IQ and skin color is of no greater scientific interest than a correlation between any two other arbitrarily selected traits, say, mean height and color of eyes. The empirical results, whatever they might be, appear to have little bearing on any issue of scientific significance. In the present state of scientific understanding, there would appear to be little scientific interest in the discovery that one partly heritable trait correlates (or not) with another partly heritable trait. Such questions might be interesting if the results had some bearing, say, on some psychological theory, or on hypotheses about the physiological mechanisms involved, but this is not the case. Therefore the investigation seems of quite limited scientific interest, and the zeal and intensity with which some pursue or welcome it cannot reasonably be attributed to a dispassionate desire to advance science. It would, of course, be foolish to claim, in response, that “society should not be left in ignorance.” Society is happily “in ignorance” of insignificant matters of all sorts. And with the best of will, it is difficult to avoid questioning the good faith of those who deplore the alleged “anti-intellectualism” of the critics of scientifically trivial and socially malicious investigations. On the contrary, the investigator of race and intelligence might do well to explain the intellectual significance of the topic he is studying, and thus enlighten us as to the moral dilemma he perceives. If he perceives none, the conclusion is obvious, with no further discussion.

... The question of heritability of IQ might conceivably have some social importance, say, with regard to educational practice. However, even this seems dubious, and one would like to see an argument. It is, incidentally, surprising to me that so many commentators should find it disturbing that IQ might be heritable, perhaps largely so. Would it also be disturbing to discover that relative height or musical talent or rank in running the hundred-yard dash is in part genetically determined? Why should one have preconceptions one way or another about these questions, and how do the answers to them, whatever they may be, relate either to serious scientific issues (in the present state of our knowledge) or to social practice in a decent society? [from For Reasons of State, Pantheon, 1973, p. 361-362]

Subtitute "sexual orientation" for "intelligence" here, and you have some very good reasons to be skeptical of Hamer's, Bailey's and others' enthusiasm for trying to find a biological basis of sexual orientation.  I can understand why laypeople want to know why we are the way we are, but I see no reason to fund scientific research to understand why people differ from each other.  (Why am I left-handed?  Why am I gay?  Why am I an atheist?  Why am I taller than both my parents and all of my younger brothers?  Why are some people darker-skinned than others?  Why am I attracted to this man, but not to that one?)

Hamer comes closest to offering a scientific rationale for such research: "... I am more intrigued by what the work tells us about the role of epigenetic imprinting – the silencing of genes by methylation. This imprint can pass from parent to child and has implications for a range of complex human traits."  Apparently, though, "epigenetic imprinting -- the silencing of genes by methylation" is relevant to "a range of complex human traits," not just sexual orientation.  There's no particular reason why it should apply to homosexuality (or to heterosexuality), except that traditional forms of biological determinism have failed and We've Got to Do Something.  If I recall correctly, Hamer is one of those gay scientists, like Simon LeVay, who try to justify their research by claiming that it would support gay equality in some obscure fashion.  But gay equality doesn't depend on our being born gay, and finding a role for epigenetic imprinting is not likely to persuade bigots.  What this research mainly shows is that scientists like Hamer don't really understand the role of biology in human behavior and culture -- that is, what it means, socially and ethically and politically, for some trait to be "biological" and "not a choice."

I suspect that Tuck Ngun had never thought about possible social consequences of his work until controversy erupted over his announcement.  If I'm right about that, then his scientific education failed him decisively.  (But then, if bioethicists like Alice Dreger were doing the teaching, it could hardly have done otherwise.)  Judging from the pronouncements of people like Dean Hamer, bioethics in practice largely means finding ways to ward off criticism and get more funding for badly designed research of little or no scientific value.  (Remember that Hamer also wrote a book called The God Gene, arguing for a genetic basis for religion; I don't know who was responsible for that title, but Hamer's in no position to complain that laypeople have inaccurate ideas about genetic determination when he's fostering them himself.)  But then there will always be gay people who will clamor for badly designed research of little or no scientific value that will make them feel less bad about being gay.  Where there's demand, there will be suppliers.

Model Dressed as Scientist Inappropriately Touching DNA Molecule

 

One reason I've been feeling blocked lately is that so much of what I see these days is stuff I've written about before.  When I think I should write about it, I remember I've written about it before, so why bother?  But I know that's no excuse, if only because it's normal practice; and if the same themes keep turning up in the media, they also need to be addressed anew.  (Another possibility is that I should try harder to read about different things.)

Anyway, a friend of mine linked today to an article that The Raw Story recycled from The Guardian, about allegedly new research allegedly showing a genetic factor in homosexuality.  Her comment was "Who cares?"  Many people do, alas.  And, as noted, I've written about this subject before, in posts that I think hold up quite well.

Perhaps because of this, I did a bad thing: I reacted to the article in comments to my friend's link before I'd actually read it.  Then I began reading the article and added some postscripts to my first reaction.  On the other hand, the comments to the article at Raw Story are even less well-informed than mine on Facebook.  The comments at the Guardian are not much better.  But let me say some things about the article itself.

The study in question is a followup to Dean Hamer's research from the 1990s, as the article mentions.  The relationship of Michael Bailey (who did the presentation) to this new study is not made clear.  And it manages to get some things right about Hamer's work.  Among other things:

The gene or genes in the Xq28 region that influence sexual orientation have a limited and variable impact. Not all of the gay men in Bailey’s study inherited the same Xq28 region. The genes were neither sufficient, nor necessary, to make any of the men gay.

This was true of Hamer's original work too.  What it means is that some straight men had this genetic marker, and some gay men did not.  Nor did the work establish how many gay men had the marker, or how this "gene or genes ... influence sexual orientation."  Until those questions, among others, are answered, it seems to me extremely premature to trumpet research like this as establishing anything at all -- especially since, as the article notes, it raises

the more dubious prospect of a prenatal test for sexual orientation. The Daily Mail headlined the story “Abortion hope after ‘gay genes findings’ ”. Hamer warned that any attempt to develop a test for homosexuality would be “wrong, unethical and a terrible abuse of research”.

I'm going to be harsh but not, I think, unfair: this was a tremendously stupid thing for Hamer to say.  Scientists like to claim that they're not responsible for the uses to which their work may be put, and perhaps they aren't.  But to whine, when confronted with a very likely consequence of one's work, that it would be "a terrible abuse of research," to be shocked! shocked! that it could be so used, is to reveal a detachment from reality that deserves derision at best.  Knowing what we know about the consequences of detecting a fetus's sex for sex-selective abortion, it's naive to think that being able to detect a fetus's sexual orientation would have no consequences.  (On the other hand, even on the most charitable evaluation of Hamer's research, it doesn't promise to determine sexual orientation at all, before or after birth.)  It would be less embarrassing if Hamer had simply tried to maintain a pose of Olympian detachment.  I believe (I'll try to find some citations) that Hamer has even hoped piously that born-gay research would somehow help the quest for gay and lesbian equality, probably because it would show that we didn't choose to be this way, as if that made a difference.  As I've also argued before, the moral acceptability of homosexuality, or its legal status, has little or nothing to do with its etiology, and numerous 'lifestyle choices' are protected explicitly by American civil rights law.  Hamer is evidently a very good geneticist, but when it comes to interpreting his data or thinking about social dimensions of human sexuality, he's a bit slow.

The article goes on to quote some other researchers on "the biology of sexual orientation."

Qazi Rahman, a psychologist at King’s College London, said the results were valuable for further understanding the biology of sexual orientation. “This is not controversial or surprising and is nothing people should worry about. All human psychological traits are heritable, that is, they have a genetic component,” he said. “Genetic factors explain 30 to 40% of the variation between people’s sexual orientation. However, we don’t know where these genetic factors are located in the genome. So we need to do ‘gene finding’ studies, like this one by Sanders, Bailey and others, to have a better idea where potential genes for sexual orientation may lie.”

I don't doubt that sexual orientation has a biology, just as language does.  But while biology can shed some light on the mechanisms that govern the production of language in general, it has nothing to do with languages: that I speak English instead of French or Japanese is not the result of biological differences between English speakers and Japanese speakers, but of historical and cultural differences.  One could point to some meaningless correlations, such as that Japanese speakers are more likely to have black hair and brown eyes than English speakers (though the percentages are changing as English has become a world language), but these do not indicate that black hair and brown eyes somehow produce the Japanese language.  Analogously, it's clear that human beings form preferences for sexual partners and sexual practices, but so far I have not seen any reason to believe that these preferences have any basis in biological variation.  As you can see if you read this article or most writing on "the biology of sexual orientation," these scientists have not been able to discover how these genetic markers or other factors produce a partiality for male or female partners -- because they are generally unaware of such partiality as a psychological factor, and assume that biological femaleness (for example) automatically produces a desire to be penetrated in both males and females.

Rahman also makes a very elementary mistake in his quoted remarks: the degree of "heritability" of a trait does not necessarily say anything about the mechanism of heritability involved.  Heritability is a complex factor that I don't pretend to understand, but then it's not my profession to understand it.  Different scientists differ on what the concept even means, and the terminology itself leads to confusion, as numerous scientists have pointed out -- Richard C. Lewontin, for instance, in his review of Evelyn Keller's The Mirage of a Space Between Nature and Nurture:

A major problem in understanding what geneticists have found out about the relation between genes and manifest characteristics of organisms is an overly flexible use of language that creates ambiguities of meaning. In particular, their use of the terms “heritable” and “heritability” is so confusing that an attempt at its clarification occupies the last two chapters of The Mirage of a Space Between Nature and Nurture. When a biological characteristic is said to be “heritable,” it means that it is capable of being transmitted from parents to offspring, just as money may be inherited, although neither is inevitable. In contrast, “heritability” is a statistical concept, the proportion of variation of a characteristic in a population that is attributable to genetic variation among individuals. The implication of “heritability” is that some proportion of the next generation will possess it.

 Back at the Guardian, Qazi Rahman continues:

Rahman rejected the idea that genetics research could be used to discriminate against people on the basis of their sexual orientation. “I don’t see how genetics would contribute more to the persecution, discrimination and stigmatisation of lesbian, gay, bisexual and transgender people any more than social, cultural or learning explanations. Historically, the persecution and awful treatment of LGBT groups has been because politicians, religious leaders and societies have viewed sexual orientation as ‘choice’ or due to poor upbringing.”

Rahman is even more embarrassing than Hamer.  Of course genetics research could be used to discriminate against people on the basis of their sexual orientation.  Such research has already been used to justify discrimination against people on the basis of their sex, skin color, class, level of intelligence, and other traits; why should sexual orientation be any different?  Rahman is historically ignorant, and probably dishonest to boot -- it's hard to believe that any educated person nowadays could be completely unaware of the twentieth-century history that belies his claim.  But hey, The Two Cultures and all.  His second quoted sentence supports my suspicion of dishonesty, in the way that scientists often try to pretend that their work has no social consequences because they're ignorant of those consequences and prefer not to think about them.  This reminds me of Noam Chomsky's criticism of scientists who try to brush aside questions about the social consequences of their research:

Similarly, imagine a psychologist in Hitler's Germany who thought he could show that Jews had a genetically determined tendency towards usury (like squirrels bred to collect too many nuts) or a drive towards antisocial conspiracy and domination, and so on. If he were criticized for even undertaking these studies, could he merely respond that “a neutral commentator ... would have to say that the case is simply not settled” and that the “fundamental issue” is “whether inquiry shall (again) be shut off because someone thinks society is best left in ignorance”? I think not. Rather, I think that such a response would have been met with justifiable contempt. At best, he could claim that he is faced with a conflict of values. On the one hand, there is the alleged scientific importance of determining whether in fact Jews have a genetically determined tendency towards usury and domination (an empirical question, no doubt). On the other, there is the likelihood that even opening this question and regarding it as a subject for scientific inquiry would provide ammunition for Goebbels and Rosenberg and their henchmen. Were this hypothetical psychologist to disregard the likely social consequences of his research (or even his undertaking of research) under existing social conditions, he would fully deserve the contempt of decent people. Of course, scientific curiosity should be encouraged (though fallacious argument and investigation of silly questions should not), but it is not an absolute value ["Psychology and Ideology", in For Reasons of State (Random House, 1973), 360].

So what is the scientific significance of discovering that homosexuality is correlated with finger length?  As Chomsky says of racial science, one would like to see an argument.

One other thing I should point out: the study mentioned in the Guardian/Raw Story article has not yet been published, which I take to mean it has not even passed peer review yet.  Why should it be touted in major media at all, when it's not even certain that it will stand up to this most basic scrutiny?  This is an unfortunately common tendency in mass-media science reporting, where the presentation (in this case by a notoriously publicity-hungry academic of doubtful ethics, Michael Bailey) makes grandiose claims that mysteriously vanish by the time the study sees print -- if it ever does.  But it's the initial headline that will be remembered and passed along, not the later correction.