Tuesday, January 04, 2005

Yesterday turned out mostly as expected: work, a bunch of stops on the way home, dinner, homework, bed. I know everyone is thrilled to read about my exciting day.

So instead, I have some reading assignments for everyone:

I often criticize our foreign policy, but I will never be critical of our generosity to the misfortune of others. I can think of no example of a natural disaster when the United States failed to contribute more to relief and rebuilding than all other nations combined. The current relief effort after the tsunami is no different. And, playing its part perfectly, the completely inept UN is critisizing the US and Australia for doing too much too fast, thus robbing the UN of the opportunity to take credit for our work while contributing nothing. The inside story is here.

This is a very long piece on why the Democrats don't seem to be able to win elections. I know I said no more election stuff, but again, if I were a Democrat, I would be demanding answers from my leadership.

Homosexuality seems to be the fascination du jour among evangelicals. I have never understood why this one topic dominates religious discussions other than the political bona fides (in evangelical circles, at any rate) that can be had by self-identifying as an extreme homophobe. I am not questioning whether or not homosexuality is sin; I firmly believe it is. However, I don't see it as "worse" of a sin than any of the other sins frequently listed by Paul in the New Testament. Where is the righteous indignation against gossip and divisiveness? Both of these are arguably far more damaging to the church (and the Church) than the presence of even an openly homosexual individual. An attitude, by the way, which puts me at odds with 99.999% of evangelicals, including my own church.

This topic has been much on my mind lately for the simple reason that there seems to be a growing (or maybe it is just my awareness that is growing) confusion about sexual orientation and sexual roles among the high school teens I deal with. I understand that there always has been and always will be a certain amount of exploration and curiosity among young people, and that the current climate of acceptance results in more open expression of that. Maybe that is all I am seeing; verbalization and even acting out of what, when I was in high school, took place only in people's minds or under extreme secrecy. Or maybe not. Maybe this is something we need to look at more closely.

So why am I bringing this up now? It seems that I am not the only one kicking this topic around in my head:

First, Jerry Pournelle shares a conversation he had with Greg Cochran. Mr. Cochran attributes many things that are commonly blamed on genetics, to pathogens. While he is outside of the mainstream, he has made a compelling case for many "genetic" diseases. In any case, here is the conversation:

The following is the result of a discussion in another forum, and was written by Greg Cochran in response to discussions over the past couple of weeks. After a fairly long discussion of competing theories on the causes of homosexuality, I said:

There is another problem: is it possible that there are at least two kinds of homosexual men, and possibly more? What is the evidence for assuming that all such people have equivalent motives for their -- I hesitate to say aberrant, but no better word comes to mind at the moment -- behavior? Clearly there is circumstantial homosexuality, as encountered in prisons, and I am told of cases where men become queens and exhibit quite feminine characteristics, but on release, go back to heterosexual ways; indeed, didn't Kinsey write about such? Now that is obviously quite different from the men who have never found women attractive and have always been drawn to other men, and probably different again from the hedonistic bi-sexuals who seem to go both ways and enjoy it, and I know of at least two such people.

Perhaps in the search for the causes of homosexuality we pursue what doesn't exist, because there is no single "homosexuality" at all, but several syndromes which produce similar results -- after all, there would be cultural molding wouldn't there? Certainly in New York in the 50's there was a gay culture, easily identified, and which demanded conformity. I saw it at work from my position in off-Broadway theater.

Cochran's hypothesis comes simply from statistical fact: homosexuality is such a heavy genetic burden that it ought to be bred out of the race rather quickly, and remain quite rare. Instead there seems to be a rather small but steady percentage, not Kinsey's 10% but not vanishingly small either. Infection as a cause doesn't seem unreasonable; surely no more unreasonable than postulating genetic tendencies.

My guess is that before we can learn more about this subject we have to take the trouble to define what we are studying, and examine whether or not a homosexual is a homosexual is a homosexual. I'd guess there is more than one variety and there may be more than one "cause".

Greg Cochran responded:

Sure, post away, and of course put my name on it. I'll bet you that most homosexuality has a single cause: why suppose otherwise until we find evidence for it? I can think of none. I will also bet there are rare cases of it being caused by a mutation, just a one in three hundred cases of narcolepsy are caused by a mutation. I wouldn't be surprised if someone someday managed to stumble onto a toxin that causes homosexuality, just as that China White heroin derivative caused Parkinsonianism.

A pathogen cause is much more likely than a genetic one, because natural selection tends to make silly genes like that rare. it does not necessarily tend to make us immune to a pathogen, because the pathogen is furiously evolving counters to our new defenses.

Gregory Cochran

I point out that my "multiple varieties" hypothesis is not inconsistent with Greg's "most homosexuality has a single cause;" my caution was more directed toward designing experiments that will be not be spoiled by a few cases outside the hypothesis of the experiment. His original comment follows:

Subject: Sheep

Right now I lean against the idea that the hypothetical bug causing homosexuality is primarily transmitted by homosexuals: it need not be a persistent infection either. Look, this is medicine, not physics: we need to look at examples at least as much as consider first principles. First principles (neodarwinism) tell us that homosexuality is not a variant behavioral strategy like hawks and doves, not a choice, unlikely to be primarily genetic. It is unlikely to be caused by new environmental insults, since it's been around a long time- although I've wondered if a fair amount of lesbianism might have such a cause: looks as if it may. Ok; this says that some bug is most likely the key cause: but that hardly tells us everything. It doesn't tell us which bug it is or how it operates. The problem is, there are _many_ ways in which a pathogen can cause trouble, and there are a number of classes of pathogens, some poorly understood

My guess is that something has happened to the hypothalamus, specifically damage to one of the hypothalamic nuclei: probably some particular subpopulation of neurons that manufacture a neurotransmitter important in male sexual behavior. The example that inspires this hypothesis is narcolepsy: we now know that narcolepsy is caused by a deficiency of a neurotransmitter called orexin or hypocretin, one manufactured in a particular hypothalamic nucleus. We know that mutations can cause hypocretin deficiency, but such mutations only account for a tiny fraction of human narcolepsy (last I heard, only one individual out of hundreds of narcolepts tested). This is what you should expect: bad mutations are generally rare, and by rare I mean a lot rarer than narcolepsy.

Narcolepsy is a reasonable model because it affects a particular behavior/brain system and leaves everything else intact. Look, one of the important factors to consider in trying to understand human homosexuality is that it affects a very limited set of behaviors. It changes sexual orientation, seems to change speech and interest patterns, causes some increase in what I call neuroticism for lack of a better word: but it doesn't reduce IQ at all, doesn't cause psychosis, doesn't make anyone twitch or drool. If the cause is indeed some kind of insult to the brain the consequences could certainly be a lot worse. So we're talking a very _specific_ and limited insult - and narcolepsy is like that.

We know that there is a super-strong association between a certain HLA type (carried by about a quarter of the population) and narcolepsy: 99% of narcoleptics have this HLA type. We know that identical twins of narcolepts are far more likely to have narcolepsy than the general population - yet at the same time, most MZ twins are discordant for narcolepsy. Just as they are for homosexuality. In both cases, there needs to be some environmental cause.

Now there is some reason to suspect that there is something funny going on with a particular hypothalamic nucleus (INAH3, if memory serves) in homosexual men. It looks to be smaller than in heterosexual men . The right way to investigate this is not old-fashioned dissection. If you knew the neurotransmitter you were looking for, you could look to see if the neurons making it are still there. They have done this in autopsy studies of narcolepsy and those specialized neurons are just ... gone. Nobody knows why. There were only 30,000 or so of them, but if you lose them, you can't stay awake. There's no sign of scar tissue or gliosis.

The suspicion is that this is an autoimmune disease, triggered by something or other. Could be. The something or other might well be a pathogen. It could also be a neurotropic infection that > happens to devastate this particular neuronal subpopulation. We know of things like this. Parkinson's is also caused by decimation of a particular neuronal subpopulation. As far as we know, no matter what kills those dopaminergic neurons, the result is Parkinson's. A virus can do it: happened with the big epidemic of Von Economo's encephalitis back in the 1920s: caused a lot of cases. Mutations can cause Parkinson's, but they are rare. Certain toxins hit dopaminergic neurons: a bunch of junkies in SF managed to get Parkinson's disease\ from a synthetic heroin derivative.

Problems in identification:

Homosexuality could be a rare result of a common infection. That is true of many diseases: true for polio, for rheumatic heart fever, for Burkitt's lymphoma, for nasopharyngeal carcinoma in south China. Probably true for MS and lupus, true for many cases of lymphoma, true for Kaposis's sarcoma, true for cervical cancer. You can end up with a situation in which 90% of the population has had a particular bug, while 100% of those with syndrome X have: the link isn't particularly obvious. It was that way for helicobacter pylori: in much of the world, everyone ends up infected, while only ~10% develop ulcers and ~1% stomach cancer. Yet H. pylori is the key: hard to see.

Even worse ( i.e. harder to figure out) are hit-and-run diseases: those in which the causal pathogen does not persist (or at least we can't detect it) . True for rheumatic heart fever, true for Type-I diabetes. True for a number of viral agents which cause obesity in experimental animals: something has happened to the hypothalamus, it only happens in those animals that have been deliberately infected, but there is no histological sign of it upon autopsy.

We know that cows that have certain papillomaviruses and eat lots of bracken fern often develop stomach cancer: both factors are necessary. Yet often these cancers do not carry integrated papillomavirus: probably they do at first, later become mutated enough to have uncontrolled growth without viral oncogenes, then clones that lose the viral antigens evade immune surveillance and grow big. Hard to figure out a similar case in humans, eh?

Shoot, there is a respectable notion that bacterial vaginosis is actually a weird venereal disease: phages (viruses that attack bacteria) that kill the normal vaginal flora are being venereally transmitted, allowing bad bacterial overgrowth.

It gets worse. Experimental mice often suffer from a chronic lung problem: the suspect was a mycoplasma, but it was really hard to make the case. Finally (decades later) they raised mice germ- free and exposed them to various candidate pathogens. It turns out that the mycoplasma was the cause all right: but it look half a mouse lifetime to manifest, some mouse strains were far more vulnerable than others, and microenviromental differences were important. If you were slow to change the bedding, urine released ammonia and exacerbated the lung problems. That's how complicated things can get.

And yet worse: there pathogens we have trouble detecting and cultivating.. GC mentions the first archaeal pathogen: I've been predicting that such must exist, but there must be more Every few years we find a new virus. You even have to consider the possibility of cell- line infections, as in canine venereal sarcoma.

And I'm not even considering ( not here, anyway) the possibility of host manipulation. So, how do we look for the bug?

First, do the obvious: look, with the standard tools, for some known pathogen that exists in essentially all homosexual men. That's fraught with problems, they have a tendency to have higher rates of just about every venereal disease and some diseases that wouldn't normally be considered venereal (like giardiasis) - potentially confusing. But sure, do the obvious first, and do it with style. You might use representational difference analysis (RDA) to look for DNA that exists in the homosexual twin of a discordant MZ pair.

But probably you want to look at sheep. You can do anything to sheep: dissect them, expose them to candidate pathogens. Clone a homosexual ram and see if the clone is homosexual: I'll that it usually is not. Look at their brains: we know that there are differences in the amygdala, but we'd do better by looking for differences in neurotransmitter expression, using a gene-expression chip. Use RDA. Look for funny 16s rRNA. See if it's catching, in sheep. And so on.

Gregory Cochran

All of which is long and technical in places, but anyone that didn't sleep through high school biology ought to get both the gist of what Mr. Cochran is saying and why current politics will destroy anyone that attempts to investigate the matter.

Elsewhere, the AnalPhilosopher asks:

Is Homosexuality a Misfortune?

Suppose, as seems reasonable, that sexuality is unchosen. Some people are born homosexual; some are not. (The vast majority - 97% or more - are not.) Should we say that those who are born homosexual are unfortunate, just as those who are born with diseases of various sorts are unfortunate? One way to come at this is to ask yourself, if you're a parent, whether you're indifferent about your children's sexuality. Does it matter to you that your children are heterosexual? (I assume that, more than anything else, parents want their children to be happy.) Please note: I'm not asking whether you'll love your homosexual children any less than your heterosexual children. I'm asking whether, other things being equal, you prefer that your children be heterosexual.

Someone might say, "Yes, I prefer that my children be heterosexual, but only because homosexuality is looked upon with disfavor in society; if this were not the case, I'd be indifferent." Really? Seriously? To probe your intuitions, imagine your ideal society, one in which sexuality has the status of eye color. People notice eye color from time to time, but it has no moral salience. We don't discriminate against the green-eyed, for example. Are you saying that you're indifferent about the sexuality of your children in this ideal society - that, quite literally, you'd be willing to flip a coin to determine your children's sexuality? Are you saying that your children's sexuality matters to you no more than your children's eye color?

If thought experiments such as this lead you to conclude that you prefer your children to be heterosexual even where there is no discrimination against homosexuals, why do you prefer it? This may be difficult to answer, since it calls for an unusual degree of introspection. Could it be that this preference is a manifestation of a belief on your part that homosexuality is a misfortune, the proper response to which is pity? By the way, misfortune, like fortune, comes in degrees. Saying that homosexuality is a misfortune isn't to say that it's a grave misfortune, much less that it's the worst thing that could happen to a person. But it is to say that those who exhibit homosexuality, even if closeted, are afflicted.
Which is another question that cannot even be asked in certain circles without being shredded.

And finally, the writer of A Stitch in Haste blogs here about the case of a high school senior being expelled from a Christian school for running a blog discussing homosexuality. The site is explicitly not a gay dating service. It is a discussion board like millions of others. The school may have been clearly within their legal rights to do what they did, but again, my question to the school administration is "When was the last time a student was expelled for gossiping? Or creating divisions in the Church?" I went to high school, and I currently work with high school students. I can state without any hesitation that these two activities consume nearly every waking hour of the average high school student.

OK. I'm out of words.

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