6.08.2005
Interesting theory on the relationship between genes and "genetic" diseases and "genetic" predisposition
I have to credit Nick Malaya for the interesting blog link that prompted this blog entry. The link is at the beginning of the quotation. There is mention of the idea that the current view/newfound emphasis and study of genes which supposedly promote diseases/disorders is highly flawed.
As a rationally-minded person I am very interested in the theory presented by this article, although not at all because of the context that it is examined in (the "Is there something that predisposes someone to becoming homosexual / makes them homosexual?"). I think that this question is so ridiculously politicized in the cultural context of the Western world that I caution the reader to really examine the underlying theory of this article in a more medical context and entirely independently from the issue of the origins of a person's sexual activities. The idea that genes that contribute or promote certain diseases/physical disabilities are far less prevalent than thought and that we should look for other causes/factors that increases one's "at risk"-ness for certain disorders/diseases is very very interesting. The argument they present in the article are completely legitimate and rather compelling in my mind, namely along the lines of (quote source and article)
That something greater was a radical new view about the causes of disease. What Cochran suspected about homosexuality, he and his colleague now believe to be true for a large number of conditions - namely, that microbes, not genes, are responsible for them. Ewald and Cochran's innovation is to consider disease from the perspective of human evolution. If your mother is obsessed with knowing when you are going to give her some grandchildren, then you are more or less familiar with the traditional perspective of human evolution: You were put on this earth to reproduce. Anything that gets in the way of reproduction is a problem that you better be prepared to explain. To judge the size of such a problem, evolutionary biologists assess its "fitness cost" - that is, the damage it does to your chances of procreating.
The math is unforgiving. If a genetic trait has a fitness cost of just 1 percent, it will sink to the very low rate of a random mutation after only 100 generations. Over the course of human evolution (roughly 800,000 generations so far) a trait would vanish even if its fitness cost were as low as 0.001 percent. According to the best available estimates, however, 3 to 4 percent of men and 1 to 2 percent of women in the United States are exclusively homosexual. That's a lot of homosexuals. Too many, Cochran and Ewald believe, for the condition to be genetic.
Feel free to change homosexual to some "genetic" based disorder.
However, the theory, expressed only in a most brief form and examined only in its implications for the "gay gene" idea in the article(1) , becomes even more interesting (or complicated) when examined in light of a society with various classes, i.e. one where their rate of procreation is not a strict function of their DNA. I would be very interested in what the rates of occurence of genes which would have an adverse effect on procreation rate as a function of this rate would be found from a simulation that would somehow take a "wealth" factor into account along with social norms and customs of various populations of people from around 2 to 4 thousand years ago to the present, and also the implications on such a simulation in terms the potential for vast simplifiction based on the relatively low number of privledged people during different epochs of history. It would be really really interesting to do something like this for a very small sample of some European population where there are baptism records from medieval times to design an arguably more accurate model at least for that population (I assume that even if one assigned total uncertainty to the actual father of the child, or more like say 1/4 to 1/2, which I think would be a reasonable upper bound, one would find that it could still hold a lot of value) . It would be interesting to simply do some kind of simulation that would assume just some mechanism that would have some increase in random family lines that would have some frequency of leveling off (i.e. eventually someone messes up the inheritance, etc etc). I am sure there are already tools that could be built off of (such as Avida ) and I think the results could be very interesting. Maybe Greg Nelson just found an idea for his thesis for his Comp. Sci. B.S.
EDITS:
1. June 12, 2005 at 2:26PM (GMT) : To get rid of odd characters appearing in the large quote wherever an apostrophe or other special character should have been, and for some clarity.
As a rationally-minded person I am very interested in the theory presented by this article, although not at all because of the context that it is examined in (the "Is there something that predisposes someone to becoming homosexual / makes them homosexual?"). I think that this question is so ridiculously politicized in the cultural context of the Western world that I caution the reader to really examine the underlying theory of this article in a more medical context and entirely independently from the issue of the origins of a person's sexual activities. The idea that genes that contribute or promote certain diseases/physical disabilities are far less prevalent than thought and that we should look for other causes/factors that increases one's "at risk"-ness for certain disorders/diseases is very very interesting. The argument they present in the article are completely legitimate and rather compelling in my mind, namely along the lines of (quote source and article)
That something greater was a radical new view about the causes of disease. What Cochran suspected about homosexuality, he and his colleague now believe to be true for a large number of conditions - namely, that microbes, not genes, are responsible for them. Ewald and Cochran's innovation is to consider disease from the perspective of human evolution. If your mother is obsessed with knowing when you are going to give her some grandchildren, then you are more or less familiar with the traditional perspective of human evolution: You were put on this earth to reproduce. Anything that gets in the way of reproduction is a problem that you better be prepared to explain. To judge the size of such a problem, evolutionary biologists assess its "fitness cost" - that is, the damage it does to your chances of procreating.
The math is unforgiving. If a genetic trait has a fitness cost of just 1 percent, it will sink to the very low rate of a random mutation after only 100 generations. Over the course of human evolution (roughly 800,000 generations so far) a trait would vanish even if its fitness cost were as low as 0.001 percent. According to the best available estimates, however, 3 to 4 percent of men and 1 to 2 percent of women in the United States are exclusively homosexual. That's a lot of homosexuals. Too many, Cochran and Ewald believe, for the condition to be genetic.
Feel free to change homosexual to some "genetic" based disorder.
However, the theory, expressed only in a most brief form and examined only in its implications for the "gay gene" idea in the article(1) , becomes even more interesting (or complicated) when examined in light of a society with various classes, i.e. one where their rate of procreation is not a strict function of their DNA. I would be very interested in what the rates of occurence of genes which would have an adverse effect on procreation rate as a function of this rate would be found from a simulation that would somehow take a "wealth" factor into account along with social norms and customs of various populations of people from around 2 to 4 thousand years ago to the present, and also the implications on such a simulation in terms the potential for vast simplifiction based on the relatively low number of privledged people during different epochs of history. It would be really really interesting to do something like this for a very small sample of some European population where there are baptism records from medieval times to design an arguably more accurate model at least for that population (I assume that even if one assigned total uncertainty to the actual father of the child, or more like say 1/4 to 1/2, which I think would be a reasonable upper bound, one would find that it could still hold a lot of value) . It would be interesting to simply do some kind of simulation that would assume just some mechanism that would have some increase in random family lines that would have some frequency of leveling off (i.e. eventually someone messes up the inheritance, etc etc). I am sure there are already tools that could be built off of (such as Avida ) and I think the results could be very interesting. Maybe Greg Nelson just found an idea for his thesis for his Comp. Sci. B.S.
EDITS:
1. June 12, 2005 at 2:26PM (GMT) : To get rid of odd characters appearing in the large quote wherever an apostrophe or other special character should have been, and for some clarity.
# posted by Greg @ 4:46 PM 
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Great post greg. I for one really do believe in Gay rights and the true freedom of all who live in this country, but that should never stand in the way of purely academic research in the scientific community. It's good to see you not afraid to make stands on moral principles (as the entry above clearly shows) but are also willing to clearly look at issues objectively.
NM
NM
# posted by 
: 6/09/2005 12:49 AM
: 6/09/2005 12:49 AM
I feel the need to echo Nick's sentiments on the need for true freedom in a democracy, as I don't think I expressed that strongly enough in the original entry. Interesting and completely valid scientifically backed points regarding the observed occurence of complex homosexual behavior in an increasingly wide variety of species besides ourselves in totally natural settings, such as those mentioned in the article, are far from an exception to the rule, and they paint an undeniable picture of the actual state of life on this Earth, whether one believes in the existence of a higher/Absolute Reality or not. If you hold that animals do not have free will, blind arguments suggesting that homosexual behavior is in any way a perversion of natural behavior or God's creation are rather ridiculous and a shallow write off for real ethical considerations of such behavior.
I believe that a democratic government or society that wishes to criminalize some behavior, in either a codified and written matter legally or by simple social stigma, must have and present very strong logical arguments regarding how such behavior infringes on the rights of others <-> very clearly negatively impacts society; the burden of proof is upon one against any behavior in a free society by definition.
I believe that a democratic government or society that wishes to criminalize some behavior, in either a codified and written matter legally or by simple social stigma, must have and present very strong logical arguments regarding how such behavior infringes on the rights of others <-> very clearly negatively impacts society; the burden of proof is upon one against any behavior in a free society by definition.
I wonder if the fitness cost of homosexuality might not actually have been fairly small in the past, at least among rural populations. Thus, Fred might have wanted to have sex with men and didn't want sex with women, but he might well have married and had ten children in order that there be soemone to take care of him in his old age, and because of a social pressure to marry (or to become clergy or religious). The fact that he doesn't have a disposition to get sexually excited at women would not bar him from successfully reproducing with a woman, I assume. (After all, a heterosexual man is surely capable of engaging in homosexual acts. Surely some of the many Greek men who had sex with boys were in some sense "heterosexual", unless the prevalence of heterosexuality was much lower back then.) He would, perhaps, have vastly preferred to do it with a man (or maybe not, because maybe he would have thought it perverted, and while he had an urge to it, he might have not wanted to act on the urge), but could do it with a woman instead. I suppose the number of children he would have would likely be somewhat smaller if his sexual frequency were lower than that of a heterosexual neighbor, but I am not sure whether evolutionarily having 14 children is always an advantage over having a more moderate number like 8 (it's harder to feed the 14, for instance).
-Alex Pruss
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-Alex Pruss
# posted by : 6/09/2005 10:03 PM
: 6/09/2005 10:03 PM << Home
